Last we heard from former Knick John Starks, he was trying to woo LeBron James with sweet video real estate moves. Now it seems the 1994 NBA Finals star was getting his celebrity-endorsement on at a Union Square Duane Reade opening yesterday, when a drunk, amiable fan stole the show from him: "This guy filled his shirt with stuff and security caught him. While they were escorting him out, he was screaming, 'I just want John Starks' autograph!' " said a witness. The unfazed Starks continued to sign autographs, offering to babysit for a die-hard fan celebrating his birthday, which makes him sound a lot cooler than some other prominent celebrity endorsers.