Thanks for any suggestions.
Dan
By the fact that you actually received mail to the domain, then it also had a DNS entry including a MX entry and also a default catch-all mailbox, so your domain was online, maybe you hadn't created a web site for it, but that doesn't matter.
I don't get this amount of spam for websites I've had online for years.
The spammers get lists of newly-registered domains each day, then start sending email to common names at them (info@, etc). I get this for just about every domain I register.
Some older domains will have been created before they started using the daily new domain lists, so relativly spam free (providing you never put an email address online anywhere).