Hi, Jerry. The vapor barrier goes on the ground and some small, rounded stone around the edged can help keep it anchored. 6 mil poly makes a good vapor barrier. Having good ventilation for your crawl space is important and cross ventilation for the vents helps a lot.
It is mainly the water coming out of the ground that causes problems but the humidity in the house can be a problem too. Your house will probably have air conditioning so you want to maximize efficiency. Put unfaced insulation between the joists to keep the cool in. Even with the A/C taking a lot of moisture out of the air in the house, it will still breathe and you do not want water trapped under the floor or in the insulation. The foundation vents will let the moisture out of the crawl space.
For the few months when it does get cold, you can close the vents or just do it partially. I lived in Tulsa for 6 years so I know a little about the weather there. It's either hot or cold and there ain't nothing to block the wind all the way from the Canadian border but 3 strands of barbed wire and 2 of them are down.