I found the few illustrations of tcp attacks in "Building Linux and OpenBSD Firewalls" very instructive. Excellent book (Wes Sonnenreich and Tom Yates); the Teardrop attack was, umm, hillarious. I think it was patched a few years ago, but I'm not sure about that...
mental note: when coding a program that accepts data from a source that could have possibly come from a user,
always always always check for validity....
Generally any book that explains the details of securing a system from attacks will cover a lot of groundwork about how attacks work. Elias Levy, ?the? moderator for BugTraq, recommends "Hacking Exposed" which I took a brief look through a few years ago.
Interview with Elias I don't want to get shot at for being a script kiddie, so I guess I'll stop here... I think I want to do network security when I grow up....
-t.