Call 18004MYXBOX and have your serial number ready. I'm going to do it when I get home.
edit: Rhett I'd call them. They said mine is still under warranty so they'll replace it for free (usually costs 79 dollars). Only thing I have to pay for is shipping it to Kentucky.
Check out this (
http://www.freewebs.com/xboxdrives/) site to tell if you have a Thompson drive or not.