http://forum.midiaddict.com/viewtopic.php?t=35903
This is a thread from the Future Music forum which I linked somewhere else here regarding compressors. This thread also has some usefull (well-known) tips regarding mastering too. It's interesting because it also mentions specific tools to do the jobs.
You may need to know how compressors,limiters and EQs work in general before reading though.
