www.secinf.net
www.windowsecurity.com/whitepaper
Don’t be fooled by the name of the Web site - the Network Security Library is an excellent source of free online books, articles, FAQs, and how-to’s on many subjects, including Windows, UNIX, Netware, firewalls, IDs, security policy, the Internet, the National Computer Security Center (NCSC) and DoD Rainbow Series, harmless hacking, and many more.