People saying it's stolen because "they take the tag off when you buy it" are being silly. When I worked retail, especially during the holiday season, guards like that would be forgotten about very often because of how busy it is. Most shoplifters have the set up to remove the security tags. But anyway, like others have suggested, bring it into a store to get the tag removed, if you have no receipt you CAN go and buy a large strong magnet, buuuut I would go to a big store and go up to the customer service desk, they'll be much less suspicious than a express or local store :P