SQUID Frequently Asked Questions
Detailed Squid FAQ
Calamaris — Squid log analyzer
Parses logfiles from Squid, NetCache, Inktomi Traffic Server, Oops! proxy server, Novell Internet Caching System, Compaq Tasksmart or Netscape/iplanet Web Proxy Server and generates a report.
Do-It-Yourself Caching: Squid 2.3
A little old, but seems to be a pretty detailed tutorial on getting Squid running.
Squid 3.0 Configuration Manual – Contents
Detailed reference manual on all the Squid configuration directives.
Brief intro to get started with Squid using some really basic settings.
A page that allows you to generate pages with defined expiry/last modified headers to test a caching configuration.