"You can find out if your site has been identified as spreading malicious software ("badware") by checking the Summary page for the site in webmaster tools. (Note, you need to verify site ownership to see this information.)"
and
"All appeals and reviews are handled by StopBadware.org. Please send an email to
[email protected] explaining why you think your site was mistakenly identified or how you have modified your site."
http://www.google.com/support/webmas...y?answer=45432