How Do I Deauthorize My iTunes Account on an Dead Computer,when I mean Dead it won't turn on anymore..Now how can I do it remotely from my MacBook Pro?
Yes, unfortunately, not only can you only do it 1x/12 mos, but you need to have five computers authorized to do this, AFAIK? Here are the official instructions
So you can either contact Apple or just not worry about it (since once you have enough computers for it to matter, then you can follow the de-authorize all instructions).