Don't know how far you want to go to ride. There is a ATV rental in Brooksville You can rent and they will take them to Croom Motorcycle Park. It's a 2600 acre park in the forest. riding includes a sand pit of front trails through the woods and several old phosphate mines to ride in. check out their web page here
http://croomatvrental.com/Seen that, and seems like it would be worth the trip, but I can't justify spending $300-$400 per person.
Thanks though.