In response to Dogslayer's last post:

I think your right, airguns have come a long ways in the recent years to the point where their making them in .50 cal. In fact a read a story about a man who shot a full grown elk with a .50 cal. airgun (of course he was about 25 yds. from the animal). So i definatly encourage people to buy at least some type of airgun. If for nothing else than just target shooting.

But about the whole hunting thing and calliber and all that.. i have a daisy .177 pellet gun that shoots something like 640 fps and i have shot everything from birds, red squirrels, chipmunks, and moles with that gun. And i've found that head shots definatly do work, although i have shot squirrels in the heart/lung area and have not need a second shot. The most ideal shot in my opinion however is right throught the ear because the pellet has to travel through little bone and go almost directly to the brain ensuring an almost instant kill, IMO.

I haven't looked at any of the other suggested guns listed so far but i have found this gun... http://www.airgundepot.com/crosman-quest-1000.html
Its a .177 pellet rifle that shoots 1000 fps. And its only $99. For what your hunting this should do the job without question...im not sure if you can mount a scope on it though...

good luck and have fun