Fashion Rocks, the annual style and music extravaganza, dazzled NYC with a slew of celebrity performers and presenters last night. Stars including Jennifer Lopez, Fergie, Usher, Carrie Underwood, Jessica Alba and a glowing Nicole Richie (sans babydaddy Joel Madden) turned the sidewalk outside Radio City Music Hall into a catwalk. With performances by some of the biggest names in showbiz - including Avril Lavigne, Ludacris,Jennifer Lopez and Maroon 5, the night celebrated fashion and music in a concert event to be broadcast nationwide tonight on CBS at 8 p.m. Inside, Radio City host Jeremy Piven helmed the eveningâ€™s performances (although insiders tell Us he was a bigger diva than the supermodels strutting the catwalk under the Bryant Park tents). Aerosmith's Steven Tyler and Joe Perry teamed with Fergie for an appropriately fashionable rendition of "Walk This Way," while everyone's favorite Oscar-winning American Idol,Jennifer Hudson enlisted Perry for help on a cover of the Beatles classic of "Come Together." We spotted Hills hillbilly hottie Justin Bobby Brescia at the bar right after the show, but his small-screen sweetie, Audrina Patridge, was nowhere to be seen. How long did it take style icon and designer Kimora Lee Simmons to get ready for the night's festivities? "Too entirely long. It's two hours for hair, wardrobe, and-make up. It's two hours and fifteen minutes if there is a wardrobe malfunction," she joked with Us.