I have an 02 with 78k on the odometer and it runs great!
If money spent is not an issue, just buy a rubicon and get it over worth.
It comes with dana 44 front and rear axles, 4.10 gear ratios, 4.0:1 transfer case, front and back lockers, and some other stuff I don't know what. The rubis started in 03, I'd get the 04. If you end up getting an older one, make sure it has a rear Dana 44 as Rawk stated, the 6cylinder is a must.
I would purchase a stock Jeep and start building from there. There are too many mods available and you want to make sure everything you put on your Jeep is everything you want on your Jeep.
And let us know when you go wheelin so we can go together. Especially if your local to San Bernardino Area. There's trails all over the place here!