Best Buy Geek Squad Black Tie Protection Plan Sent me a notice that I could extend my warranty on an LCD TV that I never bought! Joplin, Missouri

They may not have been able to find a SKU number because the model is discontinued. I see three possible situations here that might be the case-
1. The mail might be spam, sent out by a company other than Best Buy in an attempt to get you to write them a check. This does not mean that the name and address CAME from best buy. It just means that someone got hold of your information (perhaps through a phone book even) and is POSING as best buy.
2. If you have a rewardzone card, you may have loaned the card to someone else in order to get points for their purchases, and then forgotten about it. If you go to Best Buy and ask them to look up your transaction history, they will be able to tell you if someone used your card info to make a purchase.
3. Do you have any kids and/or transient friends? Some people, such as kids at college, do not want to give their dorm address because they know that they will not be living there in 3 years when the plan expires. Instead, they use the address of a friend or family member with a more permanent address.
Employees at the store can look up rewardzone accounts with just a phone number. Since we do not distribute the information, and having purchases put on your rewardzone card costs you nothing (and actually helps you get free gift cards) we do not ID people to make sure that the card is actually theirs.