Two suggestions:

Encrypt your mailto address on your site. It'll thwart the 'bots' that harvest it. Here's a link to a free service: http://www.siteup.com/encoder.html

Then, since you've already made some lists, go to http://www.mailwasher.net. Use the program to download your mail. It allows you to "bounce" mail back to the spammer - he thinks you don't exist, and with luck, you'll be off that list. There's a preview function, and the ability to set up filters, as well.

Save a few of the spams. There are instructions on the net for reading headers. They can hide a lot of stuff, but ultimately, one of the machines will tell on 'em.

Then you can complain up the kazoo. (Uh, carry any complaint as far up the network as you care to.)

Hope this helps.

Mary