Here's a link to an outstanding, even entertaining, site on rules. The Squash Official (TSO) is a Canadian forum that focuses solely on rules and refereeing.
http://www.squash.ca/e/officiating/tso/
You can also submit questions to the editors, who are National / International referees. I've actually met Barry Faguy at a past Tournament of Champions -- a really great guy.
I'm also happy to answer any questions you may have through this thread.
Hannu

I'll chime in to say that
I'll chime in to say that I've been reading TSO for a few years and enjoy it and its format. For anyone interested in the rules (or their nuances), this site has a wealth of information.