Those are a lot of questions, and I'm too lazy to write a long answer. It requires too long and too detailed an explanation. I really educated myself on how to wash and wax a car properly using Auto Geek's tutorials. You can read everything you ever wanted to know about taking care of the exterior of your car here:
http://www.autogeek.net/detailingtips.html . This includes an explanation of sealants versus waxes. I can't comment on Turtle Wax or G-Wash, though, since I never used the stuff. In terms of wax, I've used products from a company called Optimum (you can buy it on Auto Geek). I use their sealant and their liquid wax, and it stays on the car for a good solid five months, from my experience. I hear the Meguire's is great, too, but I've personally never used it.
P.S. I have a co-worker who lives in the Fairfield County part of Pickerington.