The Net-Abuse FAQ by Scott Southwick and J.D. Falk. A most excellent piece of work.
The alt.spam FAQ (HTML page) or "Figuring out fake E-Mail & Posts" (ASCII mirror) This article, posted periodically by Gandalf to a number of newsgroups, describes how to find out where a fake post or e-mail originated from.
FAQs about Spam and e-mail marketing from The SpamCon Foundation.
Email Abuse FAQ, Email Abuse Resources, and the Address Munging FAQ: three excellent documents by WD Baseley. Some very fine FAQs indeed.
Spam canceling: explanations, CancelFAQs, Spam Threshholds, and the Cancelmoose[tm] bot.
Marjie's Spam FAQ, an excellent collection of information and resources.
How do spammers get people's email addresses?, with a good list of resources at the end.
FAQ Collection from Pete Moss Spam News
There are also abuse FAQs available by FTP at RTFM.MIT.EDU
times since May 25, 1998.