Definitely shop around and make sure to have it inspected by a mechanic b/f you buy. If there are problems it can help with negotiating on the price. I am down in austin, which there just aren't a whole lot of jeeps for sale. I had drive about 1 1/2 hours out of town to get my recent jeep. IMO, the TJ models have almost appreciated in value since the JK's came out. At least that is what it seems. I sold my 01 3 years ago with only 70000 miles on it, for 10k(2 inch lift with 32's). That was the going rate at the time. This time, I had a lot of trouble finding anything close to those miles under 10k. Luckily, my patience paid off, and I scored an 05 TJ with 82K for only 10,900.
I also recommend buying a stock jeep, running it stock on the trails for a bit. this way you will see exactly what upgrades/mods you want to have done. It's fun to build your Jeep the way you want it!