Saturday, February 14 in NYC: Amanda Bynes and Ivanka Trump dancing until the wee hours at La Perla's after party at 1OAK.
And in LA: Funnyman Seth Rogen looking trim and buying Valentine's Day groceries at Whole Foods in West Hollywood… Rosario Dawson introducing Eve Ensler at a performance of "The Vagina Monogues" at USC.
VIEW THE PHOTOS: Week's Best Star Sightings: February 14 - 20, 2009
Sunday, February 15, in NYC: Whitney Port working it in "The City" with her boss, Diane Von Furstenberg, and at the after party for the designer's DVF Fall 2009 Collection at New York Fashion Week… Amanda Bynes, Gretchen Mol, Brittany Snow and more at the launch of Alexander McQueen's McQ Alexander McQueen for Target collection at St. John's Center.
Monday, February 16 in LA: Paris Hilton celebrating her 28th birthday with sister Nicky and pals including Aubrey O'Day, JC Chasez, Tyrese and ex-boyfriend Stavros Niarchos at Butter Restaurant on Lafayette Street.
VIEW THE PHOTOS: New York Fashion Week Fall 2009
Tuesday, February 17, in LA: Chris Noth, "Sex and The City's" Mr. Big, in Beverly Hills… former MTV VJ Jesse Camp running errands at CVS in West Hollywood.
Wednesday, February 18, in NYC: Victoria Beckham and her entourage flying to LAX on the same American Airlines flight as Eva Longoria (who was sans entourage) – the two were escorted on to the flight just before take-off… Pam Anderson taking the runway in a gold swimsuit at pal Richie Rich's fashion show.
And in LA: Mel B working up a sweat at Barry's Bootcamp in West Hollywood.
VIEW THE PHOTOS: The Latest Star Sightings
Thursday, February 19, in NYC: Tori Spelling in turquoise on her way to Tenjune Bar from the fashion week tents… Newly engaged star Rachel Bilson celebrating with designer Brian Reyes at 1OAK.
And in LA: Mariah Carey in a sleeveless ball gown at Lionsgate Studios in Santa Monica.
Friday, February 20 in NYC: Vogue editrix Anna Wintour spotted out and about at the close of New York Fashion Week, chatting with friends before heading over to fashion week hotspot Tenjune.
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