From the red carpet to the streets, stars stepped out on Monday dressed to rock and shock and RadarOnline.com has all the photos in our daily fashion feature.

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Justin Bieber's gal pal Selena Gomez sizzled on The Late Show with David Letterman, wearing a to-die-for Emilio Pucci mini. The lace sleeved and leather accented mini dress clung to her curves in the most divine way possible, while her zipper adorned heels scored her a flawless finish.

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Steven Tyler hit the American Idol PaleyFest dressed to shock (not rock) in tacky and wacky threads. Wearing leopard bell bottom jeans with a nude leather jacket, brown boots and a long scarf, the Aerosmith frontman looked just a tad worse than fellow judge Randy Jackson, who paired a psychedelic neon scarf with a black leather biker jacket, jeans and metallic cowboy boots. 

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At the 2011 School of American Ballet Winter Ball in NYC Michelle Trachtenberg looked marvelous in a lilac embroidered Marchesa gown, which she paired with a clutch from the same collection and David Yurman earrings, while Kelly Rutherford looked Gossip Girl glam in a sleek one-shoulder gown, which featured embellished detailing.

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Kristen Wiig ravished at the Los Angeles premiere of Paul, wearing a flirty Stella McCartney Wrap dress with Roseark jewels and Rene Caovilla heels.

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Other a la mode misses included Kate Moss, who dressed up for St. Patty's Day early in a neon green gown, Olivia Munn, who stepped out in figure-unflattering duds and Janice Dickinson, who sported a putrid purple and puke green look.

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Who else rocked and shocked on the fashion front on Monday?  Click here to find out.