Power to Choose Website offers comparisons of the rates of 50 or so Texas electricity providers:
Power to Choose
Keep in mind that there are certain fees that all providers in an area are required to charge. Sometimes power companies don't include these charges in their rate quotes, and sometimes they do. If they do, then the more power you use, the less those fees affect your final bill.
I pay about 8.6 cents/kWh through Champion Electric on a 1-year fixed rate contract, before fees. With the fees, at my usual level of usage, I pay about 9.2 cents/kWh.