Carey sparkles at a Las Vegas party as stars across the country celebrate New Year's Eve. Plus: Paris Hilton, Ashlee Simpson and Avril Lavigne

BUBBLY NEW YEAR

With a glass of champagne and a party at TAO nightclub in Las Vegas, Mariah Carey has everything she needs for New Year's – except a resolution. "I should have them, but I've already done them," she says, noting she reached her diet goals in 2007

PARISIAN PARTY

Paris Hilton toasts the New Year at LAX nightclub in Las Vegas with help from her sister Nicky – and surprising new pal Kevin Federline, who joined Paris in the DJ booth in the wee hours of 2008.

DJ ASHLEE SIMPSON

Joining boyfriend Pete Wentz in the DJ booth at The Shore Club in Miami, Ashlee Simpson rings in the New Year at a party so packed the fire marshal had to turn people away.

LAVIGNE LAS VEGAS?

Not until the party's over, anyway, as Avril Lavigne pops the bubbly at a New Year's Eve celebration at the newly opened Prive Las Vegas club at the Planet Hollywood hotel.

SISTER, SISTER

Viva Las Vegas! Beyoncé Knowles and younger sister Solange shimmer down the red carpet at the opening of Jay-Z's newest 40/40 Club inside Sin City's Palazzo hotel.