They run anywhere from just over $300 up to $1199 for the big 80 gallon 18.1CFM (at 100psi!) unit.
They aren't the cheapest compressors out there. But, they'll last you a lifetime, and you won't pull your hair out every time you use a tool for 10 seconds and have to wait 1 minute for the compressor to catch up.
At one point, I thought my cheap crappy compressor was fine since I barely used it. But.. I barely used it because it sucked and wouldn't drive most of my airtools properly. Good airtools are cheaper than their comparable electric counterparts, so a good compressor eventually pays for itself if you're buying a ton of power tools. Additionally, there are airtools that you can't even get in electric versions, or the electric versions suck (like air hammers, nibblers, shears, rod blasters, etc).
My $30 air hammer gets used all the time. I've used it for chiseling stone and concrete, spending 5 minutes instead of 5 hours. And it works awesome with the custom bushing hammer I welded together out of an old socket and a cut off chisel. Makes REALLY quick work of getting pressed in bushings out without damaging anything.
In any case, I'm a big believer that you get what you pay for. I've probably returned half the crap I've purchased at Harbor Freight, Northern Tool, and Homier. Some of it is decent quality stuff with a couple of cheap parts on them that fail and then replacement parts are impossible to get. On the worse end of it, some of it is downright dangerous. My Homier table saw almost cut my finger off several times because the blade guard was unusable and it was impossible to square the fence, so the wood would catch in it and make dents in my garage door. I bought a harbor freight sandblaster yesterday which went back today because it would not feed properly without a second person shaking it. The hose clamps that came with it were garbage, one broke while I was putting it together. If one of the clamps for the blaster hose came off while using it, it would probably cause some very very serious injury. My neighbor had a Harbor Freight engine stand with 3 wheels rated for 700 pounds. He had a 450 pound engine on it and it tipped over on his leg. Broke his fibula in 5 places, and his tibia in 3. He almost lost his leg. The best thing about it... it's happened to at least 5 other people and Harbor Freight still hasn't pulled the product from their shelves.
Sorry to rant. But cheap crap pisses me off. And most of the stuff you buy today cannot be bought in a high quality version. It's all junk, designed to fail at some point so you have to buy another one. Not just tools, but crap for your house like kitchen stuff and something as silly as soap dispensers. Scheides has heard me bitch about this before.
