His flashy "Barack Obama" signature or his pert "bo" initials signed by hand are hot in the autograph biz. Some of Sen. Barack Obama's felt-tipped autographs are going for $399. But beware. Because his signature is hurried with big letters and more like NASCAR star Dale Earnhardt Jr.'s than the distinctive John Hancock of Revolutionary fame, it's easy to copy. So the market is being flooded with fakes, autograph sellers tell Whispers.