try craigslist thats where I bought my 93 YJ with 106k miles for $4,100 already had lift kit, bumpers/side steps, nice rims new tires and is actually in good cosmetic shape for the year. Good luck and I have never driven a TJ but I would say from what I have seen and in the 5k price range you will be better off with a YJ 6cyl
"when the surfs good nobody works"
1993 Jeep Wrangler YJ 6cyl 4.0 Liter(my beach toy)
2007 Honda Accord V6 EX w/NAV(my everyday driver)
2001 Toyota 4runner limited 4x4(wife's ride)
Before deciding, you should determine what you plan to do with the vehicle long term:
--If you're going to stay close to stock and just want to do some mild wheeling, either model will work fine; although the TJ will ride better and does have more creature comforts.
--If you want to lift the vehilcle and want to stay cheap, it doesn't get much cheaper than a spring over on a YJ.
--If you're going to add a store-bought lift kit and want some decent flex, again the TJ will give you far more options.
--If you're going to build a suspension (such as a triangulated 4-link or 3-link), then the YJ's stronger frame has a slight advantage, although not enough to give up the comfort the TJ offers.
Other considerations are the features you want:
--Most YJ models come with the vacuum disconnect front Dana 30 (unless someone already switched it out). This axle is nowhere near as strong as a non-disco Dana 30, as there are two shafts on the passenger side. The YJ Dana 30 is high-pinion (reverse cut gears), which is a stronger set-up for the ring and pinion, as the convex side of the teeth bear the load and spread it out over more surface area. The TJ does not use a vacuum disconnect, but it has a low pinion Dana 30 (unless you get a Rubicon model, which will have Dana 44's front and rear). In either case, you are better off swapping in a high-pinion, non-disco Dana 30 out of a Jeep Cherokee.
--YJ's came with the worst rear axle ever made...The Dana 35. TJ's also came with the Dana 35, except for the Rubicon models, which came with the much stronger Dana 44 (both front and rear and with selectable lockers installed). Some Sport and Sahara TJ's also had Dana 44's as options.
--As mentioned before, the 4.0L comes with fuel injection and are bulletproof, whereas the 4.2 is carburated (fuel injection can be added for a considerable expense) and the 4.2 is prone to certain problems.
--Some of the YJ's came with crappy Pugeot transmissions, while others came with the strong AX15 and others got the AX5 (not nearly as strong as the AX15). The TJ's are standard with 4.0's 6-cylinders (or 2.5L 4-cylinders), AW4 or AX15 transmissions (both are very strong) and in some cases, the AX5 transmission (not nearly as strong).
--The YJ came with either the NP207 transfer case (weak, but only used in 1987) or the NP231 transfer cases (much stronger). The TJ also came with the NP231 or the Rubicon Rock Trac model with 4:1 ratio.
Whether you chose a YJ or a TJ, you would be wise to make sure which parts it has to fit your application, as well as avoid expensive repairs/swaps later.