Good advice. No matter what car you decide to run, start out by deciding what series and class (out of the ones your car fits into) that you want to run. The rules will dictate what mods you can and can't make.
In Texas A sedan is pretty popular and competitive. You will do fine with a fox. Class limit is I beleive 310 cu in. So even the late model f-bods have to run a 305. It is mostly 3rd gen f-bods, but a guy with a black LX hatch or Bob Hahn in his sn-95 usually dominate. Get on the SCCA web site and order a rule book. Call Maximum Motorsports once you get some direction. A Sedan is cool, carb'd and simple. Nice sized fields with good competition.