I get those mails a lot, personally I just think... "nigerian prynce" for example, when I think of those emails. I also get warnings that my account is suspected of being sold to another user and is about to be locked if I don't respond by clicking on the oh-so-completely-legitimate-and-not-at-all-dodgy link.
Best part is, although I do have an account - I don't actually have ANY games associated with that account. Only reason that account exists (assuming it hasn't been deleted since then) was because one of my brothers gave me a trail key for WOW but I never actually got around to using it because I was moving house at the time.

Basically: what JMich said :)

With the exception that the OP did what I suggested before posting, and his account (which he has) was actually locked by Blizzard.
So let's go for the 1% that something is actually happening.

I've gotten a ton of those mails into my old trash mail, despite never having an account with them nor playing Warcraft or having Blizzard account. Though I never bothered to check if the messages came from a valid address.