Short version: Call Apple Support: 1-800-263-3394
Long version: There are only two ways to de-auth on your own. One is on the machine in question, through the iTunes menu. The other is on any computer in the world, through your iTunes account. This second option is only available if you've authorized 5 machines in total, though, so it probably won't be applicable to you.
Just give them a call, and they will help you out.
Edit: Your machine being authorized won't allow the thief to purchase things on your account, though. It will just let them watch whatever movies or shows you have on the laptop. The thing I would be scared of, is if you toggled on that little box that says "Don't ask me for my password when I make purchases." Apple won't be able to turn that off for you, and if I were you I would change my iTunes password asap. In fact, I would do that regardless of anything else.
Last edited by FanIn80; 06-23-2010 at 10:58 AM.
|