My Top Choice - 80 Gallon Two-stage:
If you're bucks up, my first choice would be to get a 80-gallon, 2-stage compressor. Tons of air and the 90psi+ pressure in the tank lasts forever because the pump will pressurize it to 175 psi, generally. However, you're looking at a minimum of $750 for a "cheap" brand, around a grand or more for a "good" brand, 2-stage compressor.

My Second Choice - 60 Gallon Single-stage:
Second choice, and the one I recommend for most hobbyists, is a 220V, 60-gallon, single-stage, belt-driven compressor. You can get one for $380-$600 and they'll do a great job supplying air for your needs. They all run on 220v and usually draw 20 amps. Horsepower ratings vary, but those ratings are all B.S. as far as I'm concerned, so don't even pay attention to them. Despite what the manufacturers would have you believe, the main things to look for are air output and tank size, not the horsepower of the motor. CFM at a certain pressure is what powers the air tools, and the tank size represents a compressor's "reserve capacity", so to speak. If you have 1000 gallons at 135psi it's going to take a long, long time for that pressure to drop below your air tool's operating pressure, which means the compressor runs less frequently. If you only have a two-gallon tank, that compressor is going to be stopping and starting every minute or less, which is hard on it. Those are extreme examples, I just used them to illustrate the point. Get the biggest tank you can find and have room for.

My Third Choice - 110V Portable:
Third choice is a 25-30 gallon portable. Portables are nice and not too expensive, but they don't have large tanks and don't put out that much air. If you really need portability quite often, get one, but if it's a rare situation that you'll need air on a remote site, it's not worth the sacrifice to get a small compressor.

I've seen some portable Campbell-Hausfeld units advertised with 5 hp or even slightly more, yet they only put out 5.5 cfm at 90 psi. That's not enough for many air tools and it won't recover the tank pressure very quickly, either. My old Ingersoll-Rand 3.3 hp put out 7.4 cfm at 90 psi and it was good for most things but it could barely keep up with a die grinder and couldn't keep up with a sandblaster or orbital sander. I hate to think how bad a compressor with only 5.5 or less cfm output would do.

What I did:
Getting back to my recommended choice behind Door #2:
I did lots and lots of checking around when I was in the market for a 60-gallon vertical, belt-driven, single-stage compressor. What I found was that the "normal" store-type brands don't put out that much air. I looked at Craftsman, Sanborn, Coleman, Husky, Campbell-Hausfeld, and DeVilbiss and they were all about the same. Who knows, maybe they literally are the same? I wouldn't be surprised if one company made all of them. Anyway, they all put out about 9.0-10.0 cfm at 90 psi. Not much of an improvement over my old portable compressor, other than the increase in tank size.

Then I happened to find an Ingersoll-Rand at a Home Depot that put out 11.3 cfm at 90 psi and 14.7 cfm at 40 psi. Woohooo! It cost $450 (about $50 more than the rest) but it's a brand I trust and it had some minor-but-nice features that the others didn't. I've had it for a few years now and I'm extremely happy with it.

Belt-drive vs. Direct-drive:
Why belt-driven instead of the "convenience" of the oil-free, direct-drive style? Belt-driven compressors are much quieter and the oiling is no big deal. Also, based on the output ratings I've seen, belt-driven compressors put out more air than their direct-drive counterparts. So you have to add or change oil once in a while. So what?

Tank Size:
The larger tanks are better because the tank pressure drops at a slower rate than in a smaller tank given the same usage. That's a good thing. Get the largest tank you can.

Accessories:
As for accessories, be sure to get a regulator (most single-stage compressors go to 110-135 psi but most air tools are designed to run at 90 psi), a water trap, and be absolutely sure to use 3/8" line and fittings! I mean the true 3/8" I.D. stuff, not the ones that claim to be 3/8" but their I.D. is barely 1/4". Home Depot is a good source for the larger fittings. I think you can run 100' of hose without much pressure-drop, and with a larger compressor I don't think what little drop there is will be a concern. Quick-release connectors are a must. Also, lever-action ball valves are nice to have at the compressor output and are also very nice to have at the tank drain instead of that annoying petcock. I'd be happy to describe in more detail what I'm referring to if you're interested (with pictures), just send me an e-mail.

Decision Time:
If you're in the market for a compressor, I hope you take the information I've given along with some of your own research and make a well-informed decision.