Hi Stuart,
Was the mail from, or purporting to be from, this forum? If so it seems a little odd that a random spammer would connect you with this site. Spammers work on the law of averages and send out thousands of 'plausible' mails, attempting to imitate Flebay, apple or even a bank, hoping that a small percentage are stupid enough to answer them.
Have a careful think of somewhere you may have listed your email address and also mentioned this forum. Looking at the replies to the thread it would seem that no one else received one, so it still seems a bit odd that you did: it could be indicative of something more serious.
I don't want to alarm you but I'd create another email address and start using that and slowly get rid of the current one, especially if you can't get to the bottom of it.
Martin