Found this on Scott Hanselman's blog. The iTunes Art Importer.
It uses the Amazon.com Web Service to find Album Covers for my iTunes collection - and it just works.
That is very cool, though there may be a licensing issue with Amazon as Joshua Flanagan notes:
I've thought about using the Amazon Web Services for similar purposes, but I believe it is a violation of their licensing agreement to store their images locally for more than 24 hours. So, in order for the Album Art feature to work, you would always need to be connected to the internet, so the image can be retrieved each day it is used. Check out the License Agreement link on http://amazon.com/webservices and see if you have a different interpretation.
Well, I'm always connected. Lawyer friends, any thoughts?