Go to his website, http://www.jackthompson.org/
there are a couple email addresses there
Normally I wouldn't advocate this kind of stuff, but this guy has (imo) no right to harm other peoples lifestyles for his own personal gain. And thats exactly what it is: this guy just wants attention, he's like a little kid. It's like, if he manages to ban violent video games, and my parents are ok with me playing them (which they are), anyone in my situation gets screwed over, but all the overprotective parents are all happy, and younger people can't do jack-shit (haha) about it, because "We don't have kids so we don't know what its like." Well I do know that I'm somewhat normal and I played (and still play) plenty of violent games.
Edit: That is not actually his website, he doesn't have one, but you might as well email them and tell him to shut the hell up.