I can never find any trail locations online. I actually found my best set of trails through a fishing forum (my true passion). There's a river I visited in MA and the access to it was by dirt road. The road had a sign that said "no through way" and I said hell with that, let's see! Well, I did get through, and by just driving around that area I found some amazing off roading trails. Some of the stuff was too much for my stock X to tackle without a winch or anybody else with me, so it was pretty cool.

P.S. I'm also a (former) caver. I got the bug from my dad, who's member number 1258 or something in the National Speleological Society. He's been in books before and explored and charted caves for the first time.