12/16/2010 at 05:00 PM EST
Was she having a good hair night? Ashlee Simpson-Wentz
stepped out for a party at the Andy LeCompte Salon in West Hollywood, where the starlet helped launch the Black 15in1 product.
The singer wasn't the only well-tressed star in attendance: Vanessa Minnillo
, Taryn Manning
and more danced to tunes spun by DJ Lindsay Luv, downing champagne and hors d'oeuvres and writing their winter hair woes on a wall in the salon.
It was a boys' night out under the stars at the Los Angeles Zoo and Botanical Gardens while Gavin Rossdale
and son Kingston, 4, dropped by a bash celebrating the new Elephants of Asia habitat together. After watching Billy the elephant saunter by the new elephant barn, the father-son duo ate food served in Chinese takeout boxes, snapped a souvenir photo together in the party's photo booth and visited a kid-friendly glitter-tattoo table. Guitarist Slash also hit the opening-night party with his boys, Cash and London.
A demure Leonardo DiCaprio
, enjoying a pre-theater dinner at Delphine at the W Hollywood
with friends. Wearing his trademark baseball cap, Leo had dinner and drinks before heading over to check out West Side Story
across the street at the Pantages Theatre.
, standing on top of a booth and dancing to her own hits "Firework" and "Peacock" while partying at Las Palmas
By JENNIFER GARCIA, CARLOS GREER and MARISA LAUDADIO