As far as I know, Apple offer a worldwide warranty, so it doesn't matter where you buy it. You should have registered it though. Maybe you could chance registering it now and estimate date of purchase. If you look on the back - just under the capacity figure (30GB or whatever) you will see a serial number in tiny letters- about 12 or 14 characters long. I need a magnifying glass to make out mine, but it can be done! Good luck!