From NYC to LA, ET zeros in on where the stars are in this edition of GPS!James Franco looks dapper in a dark suit as he walks past a throng of adoring fans in New York City after an appearance on "Late Show with David Letterman."The paparazzi catches "American Idol" alum Adam Lambert leaving the Lady Gaga concert at Staples Center in Los Angeles. The singer comments on what he thought of the performance and takes the time to pose for a photo with a fan.   (ETonline.com)