Guest JTT, I put together a thread that links to many discussions of singing, as well as some links to information off Mudcat:Threads on the singing voice
I can say that each voice is unique in how it sounds and depending on how you are using it, you could need to do exercises that are different than the singer sitting next to you. It would be best to look for a good teacher in your area and have her/him evaluate how you are using your voice and then teach you what you need to do to improve it. It's different for every one, as I said. Some people need more work than others on breath support (the most basic place to begin) and some people are relaxed while others have their muscles tied in knots. It's best to get some individual coaching on this.
Alice