Basics (Read these first.)
Organized efforts against Spam
Cancel FAQs, Cancel bots, and spam threshholds
Blacklist of Internet Advertisers , Ed Falk's Spam Tracking Page, and the Mail Abuse Protection System Realtime Blackhole List by Paul Vixie.
Government's point of view of chain letters and pyramid schemes -- some things spam sometimes tries to sell you
An excellent service that will trace the sources of Spam and send an e-mail complaint to the right place.
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