Lady Gaga Signs Books After Playing Santa With 'Gossip Girl's' Blake Lively (Video)

Lady Gaga Terry Richardson Book Signing - P 2011
Stephen Lovekin/Getty Images

Lady Gaga Terry Richardson Book Signing - P 2011

It's been a busy two days in New York for the style icon, where she also opened the Gaga Workshop at Barneys and presented an International Emmy to "American Idol" creator Nigel Lythgoe ahead of her first book signing.

Lady Gaga arrived in a see-through black-lace Dolce & Gabbana at her New York book launch Tuesday night for Lady Gaga x Terry Richardson. She also teetered -- as only a true fashion icon can -- on platforms capable of creating instant vertigo.

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The renowned photographer Richardson has been following Gaga around for a year, and his candid photos promise her "little monsters" plenty of inside moments with their idol. This book-signing appearance followed the opening of her Gaga's Workshop at Barneys and presenting the International Emmy Founders Award to Britain’s Nigel Lythgoe, executive producer of American Idol and So You Think You Can Dance.

But she was also doing good. Barneys will donate 25% of sales from all items to the Born This Way Foundation, recently founded by Lady Gaga and her mother.

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Scads of celebrities played in the Gaga Workshop in Barneys on the Upper East Side. Gossip Girl star Blake Lively (of course) showed up. So did designer Alexander Wang, Project Runway winner Christian Siriano, model Carolyn Murphy, Mario Sorrenti, actors Alan Cumming and Neil Patrick Harris. 

To get your own Gaga Workshop behind-the-scenes tour, watch this video just released by Barneys that explains (kinda) the entire Christmas experiencial shopping extravanganza.