I'm looking to sell, possible trade in, my iPad 2 and upgrade to the Air. I know how to erase all the data on it, but I can't seem to find a way to disassociate it with my iTunes/Apple ID. Is there some way to do this? I Googled it and it took me to a page on Apple's site saying that I could go into my account in iTunes and go to "Manage Devices" and delete the iPad, but the article was dated May of last year and I don't see any "Manage Devices" in the current version of iTunes. It's registered to me, so wouldn't I need to let Apple know that I no longer own the device?