Jeez! Don't unsubscribe. That will just confirm your email address to them. Unfortunately, you have been added to a spammer's list and they are sending emails which appear to come from you. This is so that you get any bounced emails back to your address rather than theirs.
The only thing you can do is eitehr change your email address or wait for them to choose someone else's account. Spammers got one of my hotmail addresses and I once received 5000 of these undeliverable messages in one day.