Kevin McCullough has done some digging and may have a lead on the forger. The suspect is one Bill Burkett. And Scott Sala has some perspective from his time working for Kinkos, and links to other stories.
Meanwhile, Tim Blair sympathizes with Dan Rather's lament:
Life is so unfair. Dan tries to bring down a President with some fake documents, and all these stupid people want to do is talk about the fake documents when the real story is the crucial information contained ... in the fake documents.