Landov; Jon Kopaloff/FilmMagic; Frazer Harrison/Getty

Hollywood’s fashion elite, including Jessica Biel, Jessica Alba and Ginnifer Goodwin, flocked to the Prada Book Launch at the Prada Rodeo Drive boutique, which was transformed into a library in celebration of the 708 page book which highlights Prada fashion collections and architectural collaborations throughout the decades. But while the theme of the night may have been reading, it was all about lavishing praise on designer Miuccia Prada for all assembled in their Prada and Miu Miu finest. “I almost wore this dress to the Emmys,” Goodwin exclaimed of her gorgeous white ’50s-inspired ensemble, “I have been wanting desperately to wear it and show it off!” Newly blonde, Miu Miu-clad Emma Roberts added, “I love Prada. I think every piece in their collection never fails to disappoint. It’s always really unique and Miu Miu does the same.” Inside the party, a Prada LBD-clad Biel flipped through the tome, showing off her favorite images to friends while Alba sipped on the event’s signature cocktail and gushed about the designer. When asked what she loved about Prada, super-stylist Rachel Zoe said it best, “What don’t I love about Prada? Seriously Miuccia is a genius. Everybody wants a piece of Prada!” See images from (and buy!) the book yourself at Prada.com. –Michelle Ward

Lucas Jackson/Reuters/Landov

Make a little room, Alba, a new Jessica is about to join you as Revlon’s latest face. The cosmetics giant has announced that Jessica Biel will be its newest Global Brand Ambassador, a welcome addition to their roster of gorgeous A-listers like Jessica Alba, Halle Berry and Jennifer Connelly. The actress will begin starring in international print and broadcast campaigns in spring 2010, and will take part in Revlon’s philanthropic activities and fundraising, starting with EIF Revlon Run Walk in New York City this past weekend. Tell us: What do you think of Revlon choosing Jessica as their newest face?

Jamie McCarthy/WireImage

Banks may now be tight with loans, but let’s just say that Cartier didn’t hold back for their 100th Anniversary Celebration in America at the Cartier mansion on 5th Avenue to benefit Service Nation, which encourages volunteerism. Anne Hathaway, Kate Hudson, Jessica Biel, Demi Moore, Eva Mendes, Justin Timberlake and Rachel Weisz may have looked like a million dollars at the Cartier Mansion on last night, but collectively they had on nearly three times that amount in borrowed Cartier gemstones — and that’s not counting the bling of Sir Elton John (also in the house). Just Hudson’s diamond and onyx panther necklace alone would have set her back $905,000, not to mention her $230,000 diamond cocktail ring and diamond studs. Timberlake was a diamond stud himself, wearing an onyx and emerald panther tie pin and onyx and diamond cufflinks. “I made a joke to my stylist tonight,” said Hathaway, herself bedecked in over $500,000 worth of Cartier jewelry. “That if I lost [a piece] tonight, technically, it wouldn’t be like losing it, because, after all, I would be at Cartier. And he said [emphatically] . . . ‘No!’” Mendes concurred. “I’m very upset that I have to give back this panther ring in the morning.” But no, she wasn’t afraid of losing the ring worth $220,000. “No, they’ve got insurance for that, Love. It’s never happened, because when things are not mine, I take even more care of them.”

Upstairs at the mansion the history of 100 years of conspicuous luxury was told through a bling-tastic exhibit of bejeweled ornaments created by Cartier for J.P. Morgan, Doris Duke, Barbara Hutton, Gloria Swanson, Elizabeth Taylor, Princess Grace, Elton John’s 43 carat heart-shaped sapphire ring and more. “There was a really lovely, very modern ring for Daisy Fellowes,” said Moore, who helped Cartier announce their partnership with ServiceNation to donate a portion of the sales of their Trinity bracelet to the organization. If you can’t afford the jewelry, pick up a copy of Bruce Weber’s anniversary homage to Cartier, appropriately entitled Cartier I Love You!, at teneues.com. – Jeffrey Slonim

London Entertainment / Splash

With everyone from Mischa Barton to LL Cool J getting in on the current trend of star designers, there is one star who is definitely not trying her hand at designing– Jessica Biel. Despite internet rumors to the contrary, a rep from William Rast confirms to PEOPLE that it is not true that Jessica will be designing handbags for boyfriend Justin Timberlake’s denim line. Repeat, she will not be designing for William Rast. The fashion world’s loss is clearly acting’s gain. Tell us: Would you like to see Jessica Biel try her hand at design?

Courtesy of Target

It’s no wonder that celebs like Jessica Biel and Sophia Bush adore Joy Gryson’s chic, easy bags. As longtime admirers, we can’t wait to acquire our own Gryson bag — from Target! The latest collaboration in their GO International collection has all the details, like chunky zippers and braided handles, that we love about the high-end line, but at a price that lets us stock up. Call us obsessed, but we had to ask designer Joy Gryson to let us in on her design philosophy: “I am a real-life girl, so I make sure the bag is something I would want to carry. This line is all about special touches to make it stand apart.” Her favorite bag? It’s the woven satchel because “it’s roomy enough to fit my life on a daily basis, but not too big.” Click here to check out the whole line at Target.com.

London Entertainment / Splash

Looks like Jessica Biel wasn’t crazy about her platinum blonde locks. After filming in London on the set of her new movie Easy Virtue, the actress returns stateside — and to her normally brunette shade — in a matter of days! We must admit that we are happy to see her natural color back. It’s a great fit for her laidback style. But we want to know what you think! Tell us: What do you think of Jessica Biel’s darker locks? Do you like this look better than the platinum blonde?

Bauer-Griffin

We’ve already confessed that Rihanna is our latest fashion crush. And yet again, the singer struck a fashion high note — leaving her New York hotel toting this Kooba bag that accessorized her biker-chic look. Her Heather shoulder bag, trimmed with vivid day-glo piping, has a retro ’80s vibe that we love. You can order the same one, $465, at kooba.com, or nab a smaller version, the Bennie clutch, for a more affordable $295. And you’ll definitely be in good company — Jessica Biel, Jessica Alba and Hayden Panettiere have also been spotted carrying Kooba handbags.

jackson Lee/Ahmad Elatab/Splash new online

For years it’s been touted as the number one rule for dressing slimmer: avoid horizontal stripes. But stars all over size-obsessed Hollywood have been sporting it recently on shirts, tees — and even full dresses. Since we love the look on the celebs like Cameron Diaz, Jessica Biel and America Ferrera, featured in our new Stars in Stripes gallery, we’re really considering adding it to our spring wardrobe with a sailor shirt or two. But we want to know what you think! Tell us: Would you wear horizontal stripes?

STEVE BAGNESS/MATRIX PHOTOS

Forget showing off new looks on the red carpet — Jessica Biel debuted her golden new blonde hair today in Heathrow airport in London! Jessica’s gone from her normal highlighted brown locks to a deep brunette earlier this year, but it’s been a long time since we’ve seen her with such light locks. She is reportedly in the U.K. to film a new movie, so perhaps it’s for the role? But regardless, we want to know what you think! Tell us: What do you think of Jessica’s new blonde hair? Do you like her better with lighter hair or her normal brown?

CAD/Fame Pictures

Every morning, no matter how put-together our work outfit is, we almost always ruin it with our commute-friendly footwear. Right now, we’re bundling up with soft-soled tall boots (or even Uggs on the chilliest N.Y.C. days). We simply couldn’t make the trek to work any other way. Of course, once we’re there, we swap the sensible shoes for some stylish heels, but we can’t help but envy the women who seem to effortlessly wear their stilettos through their morning commute. And then there are the women, like Jessica Biel, who make flat-soled shoes look spectacular any time of day. Tell us: What kind of shoes do you wear on your commute? Do you wear your high heels? Do you change once you get into work?

Barnsley/Thompsett/Pacific Coast News

Just days after Carrie Underwood hit the red carpet in her affordable Aldo heels, Jessica Biel brightens up a gloomy day in L.A. with her turquoise suede boots from Urban Outfitters. We love how the boots add a pop of color to her jeans and Lauren Moffatt navy coat. Get Jessica’s Promenade Suede Boots in turquoise, purple, grey, black or mud for just $78 at urbanoutfitters.com. For a real splurge, get Jessica’s Lauren Moffatt wool coat, $541, at revolveclothing.com or save your money and try this hooded toggle coat, only $70 at delias.com.

CAD/Fame Pictures

Even though this month’s StyleWatch cover girl has been busy filming a movie (and hanging with Justin), it doesn’t keep her from looking utterly chic while running errands in L.A. Jessica Biel was spotted this week, showing off her new shag cut and a vibrant purple –a must have color for the season– Twelfth Street by Cynthia Vincent dress with flat Loeffler Randall camel boots (Cameron Diaz has the same ones!). We loved Jessica’s look so much we had to find it for you — and, of course, the look for less!

Get Jessica’s Dress!
Twelfth Street by Cynthia Vincent dress, $215, at revolveclothing.com. For a affordable option try French Connection’s Mystify Dress, on sale $93 from $158, nordstrom.com or this even cheaper tunic, $18, at forever21.com.

Get Jessica’s Boots!
While the flat “Kit” Loeffler Randall boots are no longer available in camel, you can get them in white, $685, at bluebee.com or with a 3 inch wedge in camel, $625, at shopbop.com, but try these Seychelles flat boot with buckles, $170, at shopkitson.com for a look-a-like.

courtesy of StyleWatch

For Jessica Biel’s StyleWatch cover photo (taken at an L.A. premiere), makeup artist Kara Yoshimoto Bua went for a casually polished look. “Jessica wanted her makeup to be natural and summery but with a little extra,” Bua tells PEOPLE. The “little extra” was in her lashes, as Bua applied several coats of super lengthening Chanel Extracils Mascara in Black, $26 at chanel.com. She kept the face bare, just applying Soft Pressed Powder in Azalea, $50 at chanel.com, to give her a “flawless satin finish” and Powder Blush in Nude, $40 at chanel.com, to the contours of her cheeks. She brought out Jessica’s eyes with shimmery rosewood tones from the Chanel Quadra Eye Shadow in Sequoia, $55 at chanel.com. Then she dotted Chanel Long-Lasting Eyeliner in Ebene, $27 at chanel.com, between the lashes and extended it beyond the lashline. To complete the look, she applied a coat of Ultra Wear Lip Colour in Rose Garnet, $32 at chanel.com, to Jessica’s lips. Her hair was also casual — yet glam — thanks to stylist Renato Camporo. While Jessica’s hair was still wet, he applied Kerastase Mousse Volumactive, $34 at kerastase.com, then set the hair with pin curls and let it dry for a half hour. After removing the pins, he first used a blow dryer to “open up the curls” and then used a half inch curling iron to polish the curls around her face. He made her hair really shine with Leonor Greyl Eclat Natural styling cream, $33 at beautyhabit.com.

Jon Kopaloff/FilmMagic

We saw Jessica Biel go darker a few weeks ago for her role in Powder Blue, and this weekend she showed her a polished version of her brunette look while hosting 3rd Annual Pink Party benefiting Cedars-Sinai Women’s Cancer Research Institute. Adir Abergel of Frederic Fekkai did Jessica’s hair for the event, showing off what he tells PEOPLE is a “modern shag. It’s the modern version of Jane Fonda’s haircut from Klute. The color is a rich auburn brown.” And Adir told us how he created Jessica’s low-key look for the event. He applied Frederic Fekkai Coiff Bouffant Lifting and Texturizing Spray Gel, $23 at sephora.com, all over the roots before rubbing a dime size amount of Controle Ironless Straightening Balm, $25 at sephora.com, all over her hair to the ends. Using a two inch round brush, he blow-dried all of her hair forward to frame her face with the cut’s heavy layers. To finish the look, he pieced out the ends with Coiff Nonchalant Piecing and Forming Wax to give it extra texture.

ramey; LIMELIGHT pictures

When Jessica Biel and Jessica Alba aren’t glamming it up for the red carpet, they like to keep it casual. These L.A. girls have been keeping a casually low-profile with the new Rails fidel hat. They aren’t the only celebs who love these comfortable hats — Paris Hilton, Kimberly Stewart and Matthew McConaughey have also been spotted wearing these lids around town. And unlike some star items, this hat is actually wallet-friendly. Get your own, $38, at shopintuition.com. Check out the complete Rails collection of clothes and accessories at shopintuition.com.

FAME

We always love seeing stars in something we could afford, and Jessica Biel stepped out in a head-to-toe cheap chic look this weekend! Jessica’s trendy mod printed minidress is only $54 from Express and is still in stores now! Click here to find the location nearest you. Not only is her dress wallet-friendly, so are her adorable silver Max Studio sandals, which are on sale right now for only $78, reduced from $119. Click here to buy her sandals online!

Oliver Hadlow-Martin/Splash News

We’ve been so focused on how great Jessica Biel looks offscreen — with her chic bags and dresses — that we forgot that she would have to go back to work some day! For her role in Powder Blue, which she started filming this week, the actress has dyed her normally dark blonde hair to a rich chocolate brown. Looking at her on-set, it’s a huge difference, making her green eyes pop out even more. We think she looks great both ways, but we want to know what you think! Tell us: Do you like Jessica with darker hair, or do you miss the lighter locks?

Splash News Online

Forget Justin Timberlake — Jessica Biel hit the streets of Los Angeles this week with some real arm candy. The I Now Pronounce You Chuck and Larry star carried not one, but two great black leather bags when she left the gym. We liked them so much that we had to track them down! The drawstring bag is a Carrie Valentine “Relaxed Chic” Bag, available for $390 at carrievalentine.com. And her larger satchel is the ultra-luxe Gryson Woven Olivia bag, $1300 at activeendeavors.com. Get her look for less with this Brianna Bucket Bag, $30 at amazon.com and this Woven Pocket Shopper, $43 at asos.com.

Robin Schwanke/Getty; janet gough/Celebrity Photo

In honor of Jessica Biel’s box office success — her new movie I Now Pronounce You Chuck and Larry opened at #1, beating Harry Potter and the Order of the Phoenix! — InStyle.com is taking a look back to see how the stunning actress has grown from small-screen teen (remember Jessica as Seventh Heaven’s Mary Camden?) to big-screen bombshell. Click here to see all of Jessica’s look on instyle.com.

Matt Sayles/AP

As summer heats up, we all struggle a lit bit more to keep our hair looking perfect and fizz-free. But, according to Jessica Biel, we’re just wasting our time. At last night’s L.A. premiere of her new film I Now Pronounce You Chuck and Larry, the always well-tressed actress let PEOPLE in on her hair secrets — less is definitely more! Jessica tells PEOPLE, “I’m all about beach hair. Don’t brush it, scrunch it, mess it up, let it be dirty, let it be messy, let it be sweaty. I think it looks way better than trying to straighten it, and trying to make it look nice because no matter what, it’s going to frizz, so just let it be dirty.” Nice to know that someone in Hollywood is low maintenance — at least off the red carpet!