You really have to stop buying into the JT brand of bullshit. How many people have been threatened with lawsuits by him? And of all those people, how many have actually been sued? That's just a tactic he uses to try to scare you, but everytime he uses it the effect lessens and lessens. You need to just relax. In fact, you don't even have to respond to him. Ask yourself what fraud is legally:
"Deception carried out for the purpose of achieving personal gain while causing injury to another party."
So, where was Thomson injured? How has his position weakened by giving you his autograph under the "It's for someone else" pretext as oppossed to, say, signing it at a book convention? Thompson is crazy, but isn't stupid. He knows anything he brings against you will be tossed out (which means he'd have to pay your legal fees), AND he'd have to fly to your state to go to court. Just sit back and let him scream all he wants.