The easy way out is to go to www.csskins.net, find a good model replacement for Counter-Strike. Milkshape3D will then turn the mdl file into almost any other format out there.
knackered: Please don’t give away the our secrets! The modern soldier design is Classified.
Seriously though, if you want humans, another way is with lots of $$ and buying Poser. I personally prefer www.3dcafe.com myself. In fact just the other day I needed one, so our modeller picked up two UAV models off a DOD website which looked nothing like the ultralight (non classified plane) we were trying to display, I hopped over to 3dcafe.com and there it was. I wish all days worked like that.
One magazine (UK) had poser3 on the cover last month maybe you can try to find that.
Mind that it is verry hard to get other clothing than the default clothes. (Or none of course )
Guess where I get my models now.