Go to
http://www.cabelas.com and do a site search on Beeman and RWS.
I have a Beeman SS100, which is a Chinese gun. It works well,
although the trigger is a bit heavy. Scope holds it's zero, but isn't
what I'd call well-made. Still, it's accurate, and will put a Beeman
Silver Arrow pellet through a red squirrel end-to-end. When it dies,
I'll go and buy another RWS.

For $129 though, it's fine.
I also have an RWS 48, which took me some time to get used to.
It's available in .177 and .22. Mine is a .22, and is VERY accurate with
a Burris scope on top. With the RWS HollowPoint pellets, squirrels
die instantly. The big pellets don't exit, and ALL of the considerable
energy they have is transmitted to the varmint. They die with a shot
from a 22 Magnum - but they die quicker with the air rifle!! Really!!
Note that air rifle pellets are designed to run at subsonic velocities.
They become unstable in the transsonic region. So, if you push 'em too
fast, accuracy will suffer. Some rifles are finicky about pellet choice when
it comes to accuracy. Gamo used to market an assortment pack that's
useful. I like Beeman and RWS pellets. They're more expensive, but ya
get what ya pay for in pellets.
I have a range set up in the backyard, and it doesn't disturb the neighbors
at all. The pellets make more noise hitting the steel than the gun does.
Air rifle practice is great fun, and you'll be better with a cartridge gun as a
result. You never have to worry about a flinch, and I've found, especially with
the RWS48, that any problems with technique (position, trigger press, etc.)
are magnified.
-Stretch