Hey Staff Sergeant,
I'm in Lincoln, just 20 minutes south of Beale, (I actually just moved from Plumas Lake). ^ as Yomondo stated, the Rubicon is just 2 hours east from us. But for that I would recomend a minimum of 35" tires, a winch and some armor (Ie. skid plates and side rails). Even with 35"s, the bottom of your jeep becomes a good rock polisher, in areas.
If you go as far as Truckee pretty much any exit has some trails, I recomend take the Cisco Grove exit, head north over the freeway, make a left at the "T", and your next right (before the campground). There are a ton of trails back there and you can get as extreme, or G-rated as you want. It's a good place to get your feet wet. Plus the ground up there is practically clay so in the rain you get to get nice and muddy!
There is "Prairie City" in Sac by the I-80 - I-50 exchange. It's an OHV park with all levels of trails. $5 day pass for Prairie City but it's a great place to take the lady and have lunch off the trails.
Thanks for your service and welcome, both to Jeeps and to the area.