I just recently got an iTouch and I synced it to someone else’s computer can I sync to mine now?

My computer crashed when I got my iTouch, so I just synced it to one of my friend's. I don't want to have their songs on my iPod, my computer is now fixed and running. I want to sync MY iTouch to MY computer, but when I plug it into the USB port nothing happens. Does anybody know anything about this?