There is some documentation at Tor projects on how to use Tor such as https://www.torproject.org/download/download-easy.html.en#warning However, if one would like to be very good at using Tor/Anonymity techniques then what would be the best online resources to learn how to use Tor well? (please suggest good links) What I am looking for is not just a click and go guide but something with a little more depth. For some people the proper use of Tor may be life or death and proper use would be essential. (If I hand Tor to a friend in Iran then how can he be comfortable just clicking and going? He would want documentation to KNOW that how he was going online was close to a best possible method.)
Getting a in depth guide is good, but they can never cover everything. It is important to learn the thought processes of computer security and anonymity(knowing when to use a new identity is a basic example of this). I suggest finding text in relation to that as well.
You said you found some documentation on the Tor website - there is probably a lot more if you dig for it, there is also probably a wiki somewhere on the subject (no, not the Hidden Wiki).