My PowerShot G2 does exposure control. (You can control both aperture and exposure, either with the other being automatic, or automate both.) It wasn't cheap. (Hopefully after the repairs, it'll still be cheaper than it would have been if I bought it in Australia.)
You can even do the exposure/aperture thing on the PowerShot A40, which _are_ pretty cheap now - they've dropped $200 in the nine months they've been out. The exposure's nice and precise, the aperture control typically only gives you two options about two or three f-stops apart, depending on the conditions.
Yes, the A40 seems to be like the G2 with half the pixels and fewer addon options (no flash, possibly no macro/wide/tele lenses). Though it seems more portable and less cumbersome to carry around.
Well, you can get lenses for the A40. (In that case one'd probably need a tripod as well.)
Mostly those tips are common to all photography (lighting, framing, colour). Good tips though. Good luck to you if you can afford a camera that gives you exposure control - the only reason I'm still using SLR :)