Tons of great sites out there. AR15.com has an AK section with some decent information and links to authorative sites.

Yeah AK's can make 1911's look like they've got next to nothing for options. Much like the AR series, you have to know what you're looking for. The best way I've found to do most of that is to come up with a price I'm willing to pay and go from there.

There's actually a couple of good looking AK's for sale on this site right now.

Things to look for:

Make sure the Front Sight Post isn't canted to either side!!!! Fixable, but a pain none the less.

Check the wood, look for big gouges and splits.

Ask about trigger slap for that particular weapon. Most times AK's running more than $500 won't have the problem, but check it out anyway.

Yeah you can spend a ton of time looking for various parts and at the different models. I've got a Rommy, it was a cheap buy and needed work. I'm about $200 more into it above the origional cost, but it's a damn fine weapon sans trigger slap _fix coming soon_ and they aren't hard to work on and cheap to improve.

Again, figure out what you want to spend and go from there. You can snag em' as low as $250-300 all the way up to 1K+