I have a few airguns from spring powered to pre-charged, varying from 1000 to 1800fps. I regularly hunt everything from squirrels to small hogs with them. Pre-charged guns are the way to go. From my experience the .177 is just as effective as the .22, and the .177 shoots flatter. If you want a good entry level gun, CTD recently had Ruger Air Hawks for about $80. The triggers are god awful though. If you want a high dollar gun, the Air Force Condor Extreme is nice. I have never been disapointed in mine. Be warned though, high end guns can quickly exceed $2000. A good source for anything air gun related in Pyramid Air.
Have Fun,
T2E