The whole sing-from-the-stomach thing is just about pushing with your stomach muscles to move more air faster. That, plus it focuses your attention on the muscles rather than the lungs. It's like driving from your engine instead of your fuel tank. One problem I used to have was thinking I had to suck in as much air as possible, and it was actually limiting me, not helping. I'm not sure why, but it's uncomfortable to push air out of an over-full set of lungs.

Here is Alices Threads on the Singing Voice with lots of links to threads about technique.

Vocal coaching is not going to make you sound goofy unless you want to sound that way. It can help you with volume and projection, and teach you how to keep from wearing out your voice.