The guy who was impersonating me on MySpace has had his account deleted. They acted rather quickly, once they actually bothered to tell me what they needed: I sent in the picture and the request, and the account was gone within a couple of hours.
Now that the previous "tronguy" account at MySpace is gone, I created one and took the name for myself so that the former user can't just create a new one. I put enough content up there to identify as me, and an explanation in the blog there of why I asked the former account be deleted.