There are quite a few in the area (here's a few)
* Raven Off Road
* Jolly Jeepers
* fwporc (4 Wheel Parts Off Road Club)
* Flat Broke & 4 Wheeling
I've been going out with the guys from 4 Wheel Parts (fwporc) and having a good time. I've also been thinking about attending a Jolly Jeepers meeting (They are based out of Oregon City), and seeing what they are all about... In fact we're heading out to TSF on the 16th to play in the snow/trails. This group goes out at least a couple times/month... Varying experience levels and rigs of all stages of modification (Stock to not much stock left).
Flat Broke puts on an annual poker run at Brown's Camp. They seemed to be a nice group of folks.
'04 Solar Yellow Wrangler Unlimited: 3.5" RE Superflex w/ RE Monotube shocks, 33x10.5 BFG MT's, Warn XD9000i winch, Jeeperman Trail Skids & Rear Bumper/Tire Carrier with 1/4 Panel Guards. Skid row engine skid.
NW Quadriders ATV Club