Are you just getting into riding?? They have a great harescrambles racing series here, it's called Mid-South and you can visit the website here:
MSHSS, Inc. Cross Country Motorsports Racing
We raced that series here, had a blast...sometimes the promoters for the races will let people ride their land as long as they sign a waiver....I've heard Summertown's ok for riding, more for like jeeps and that kind of stuff though...when it re-opens, Wooly's Offroad's a good place to go for trails....Don't waste your time going to Honda Hills, it's close and all, but unless they do some work on their mini motocross track and in their trails, it's not really worth the drive out there.
Hope all of that helps.