I'd say the most popular models are probably the PT-422 ($6500 w/ no attachments) and PT-425 ($8500 w/ no attachments). They just introduced a cheaper model called the PT-180 that comes in at $4500 w/ no attachments (It's very similar to my 13 year old PT-1418, see link in my signature.) They have some big honkin' diesel models that are up into the $25-30K or so range. Quite a few to choose from. The attachments are very fairly priced compared to something like Bobcat attachments, but not quite as cheap as most 3PH attachments (like in $300 for a simple bucket, around $600-900 for several different mowers, $1200 or so for augers, stump grinders, trenchers, grapple bucket, etc.). There's 40-some different attachments for these things, some of them unpowered and some hydraulic powered by the hydraulic PTO on the machine. Check out the web-site that MossRoad mentioned (when it comes back up).
In a nutshell, I'd say the PT's have capabilities and attachments similar to Toro Dingo's and all the Dingo clones (hydraulic powered machine and attachments) at about half the price, and they share the turf-friendly articulated steering with the Ventrac's and Steiners. I really like mine, even though it is 13 years old! (But then, I pretty much like anything that even remotely resembles a tractor or loader... /forums/images/graemlins/wink.gif)
Dave