Some things to keep in mind while you're shopping...
IMO...the 2008-up models are the way to go. You get the larger 5-cly. (allegedly with the head issue fixed) or the V8 option. 2009-up models have the upgraded front axle. As an off-roader...I would immediately dump any non-Adv.Pak models from my short list. This package is well worth looking for, and many owners have no idea what it is. Some sellers advertise them as "AP" models when they're not...while other sellers have no idea that their "AP" model is anything special, and make no mention of it at all. A simple look inside at the dash cluster will tell you all you need to know...if the locker button (or buttons on 09-up models) are there, its good. If not...move on to the next one. There is nothing rare or hard-to-find about the AP. Stick-shifts are not rare either. The base-model H3 is still a great offroader but, the lower t-case ratio of the AP really shines when you bolt-on 35"s and run in low range. The crawling ability is greatly improved.
Of course budget is always a concern, and I frequently see 06-07 models for $10K-$15K...and 08-10 models for $15K-$20K. I don't think there is an H3 on the planet worth more than $22K or so (including the rediculous T-prices). If you are paying cash...price is everything and you need to find an older one for a deal. However, if you are financing...you should consider buying the NEWEST, LOWEST MILEAGE one you can find. The difference in your monthly payment will be minimal (like $10/month). Also, most lending institutions will give you better terms for a newer model, compared to an older one. So you can often times get a 20K-mile 2009 for the same monthly payment as an 85K-mile 2006. So for the extra $10/mo...hold-out and get the newest one you can afford. The H3 is a very high-maintenance vehicle, and this increases sharply above 60K miles. Whatever deal you think you are getting can come back and bite you, if you get a lemon.
I'm sort of shopping for a project H3 myself, and I'm a little scared of the early 3.5L motors. I'm looking at 08-up AP models only...and no moonroof. I'm finding out that this is actually the rarest of any combination! Nearly every AP has a sunroof, and I've only seen four of them that didn't.