What KevinB said.

Also while you can spend many hundreds, or thousands if you wish, of dollars buying a high end pellet rifle there are perfectly serviceable rifles out there for $120 to $150. Add $20 in pellets, 1000 to 2000 rounds, and your set for a long time.

The best value for money IMO is in the 'single-shot break-barrel spring guns'. Your using the barrel as a lever, no worries the barrel is plenty strong enough not to be damaged, to compress a large and very powerful spring. When released the spring drives a piston that compresses the air behind the pellet and pushes it to a consistent muzzle velocity. The advantage of this system is that it is robust, durability measured in the hundreds of thousands of shots, and very consistent.

IMO it is far better to buy a package that comes with a scope. First, your usually getting a decent scope for cheap and it will be one that is engineered for the abusive forces a spring gun puts on scopes. A spring gun recoils back as the spring and piston race forward when released. But then the gun jolts forward as the piston comes to a stop. This can destroy even an expensive rifle scope if it is not specifically designed to take these forces. DO NOT mount your prized $3000 scope on a spring gun. Unless you want it converted into a scope-shaped paper weight. Most scope manufacturers make a specific line that is built for these rifles.

A couple of suggestions:
http://www.airgunsbbguns.com/Daisy_Winchester_1000SB_p/day1000sb.htm

This is a simple workhorse pellet rifle with a nothing-special plastic stock. Funny thing is that squirrels, birds and bunnies don't seem to feel insulted about being shot by such a down market weapon. Might have something to do with being skinned, cleaned, cubed and surrounded by a rich gravy in the stew pot when asked.

For traditionalists there is the:
http://www.airgunsbbguns.com/Daisy_Winchester_1000SX_p/day1000sx.htm

Same gun but with a wood stock. I must say the stock has a better feel. The warmth and heft of the wood are IMHO well worth the extra $5.

Note: I have no financial interest in or connection to the manufacturer or retailer cited. I am familiar with this particular rifle and in comparison consider it to be head and shoulders above many more expensive makes and models as a practical weapon for small game hunting, training, practice and plinking.

I identified the retailer simply by inserting the make and model into a search engine and selecting the cheapest price it produced. This wasn't meant as an endorsement of the company. You may find either rifle for less elsewhere.