Books

• SpamAssassin, by Alan Schwartz, O'Reilly

Websites and articles

• The Apache SpamAssassin Project
• SpamAssassin Readme
• Mail-SpamAssassin modules on CPAN

Configuration tips

• Mail::SpamAssassin::Conf - SpamAssassin-3.2.x configuration file
• How do I get SpamAssassin to run faster
• Network setup:
  • Using network tests to increase accuracy
  • Network Tests Latency
  • Caching Nameserver
  • DNS Blocklists
  • UsingDcc
  • UsingPyzor
  • UsingRazor

Related tools

• sa-compile - compile SpamAssassin-3.2.x ruleset into native code
• sa-update - RuleUpdates
• sa-learn - train SpamAssassin-3.2.x's Bayesian classifier

Tests and Rules

• Tests Performed: v3.2.x

Other references:

• Debian Anti-Spam Anti-Virus Gateway Email Server using Postfix, Amavisd-new, SpamAssassin, Razor, DCC, Pyzor, and ClamAV