I'm often surprised at how many abuse folks say they learned a lot from my old Net Abuse FAQ, which still exists (untouched touched since 1998, and still focused largely on usenet) at:

http://www.cybernothing.org/faqs/net-abuse-faq.html

Section 2.11 (with the ironic title of "Has this problem really been going on for FOUR YEARS?!") has a link to an old post by Russ Allbery that I'd also strongly recommend to any new folks. I re-read it myself every few years, as a reminder of why I got into this mess:

http://www.cybernothing.org/cno/docs/russ-usenet.txt

We've all been at this for more than a decade now, my friends, and though the popular protocols have changed I think Russ's rant still rings true.