The Kelly Blue Book looks at all angles of second hand and used-car pricing. It will tell you how much you should pay for almost every car that's ever been made, and is organized in an easy-to-use style by make, model, year of the car and condition.

Be aware that there are a few significant things the Kelly Blue Book isn't much good for. It doesn't provide any indication of how dependable a vehicle is, or how problematic it may be. You can get some indication of this by gauging how well the car holds its value, but Kelly Blue Book will primarily tell you pricing.

Consumer Reports and Car and Driver will tell you much of what you need to know about a car's reliability. These two magazines give you tons of useful info about used cars?life expectancy, maintenance expenses, and?point by point?which segments of the car (e.g. transmission, engine) are likely to need to be repaired or replaced, and which aren't. I also like epinions.com. You'll find a wide range of information about almost every car that's ever been made, written by real people. All three of these resources are great because of their thoroughness and neutral bias.

Of course, none of these are enough. The Kelly Blue Book will tell you how much to spend, and Consumer Reports, Car and Driver and epinion will tell you strengths and weaknesses of the cars you're interested in. But we also suggest getting the car examined by a mechanic you trust. And trust yourself to find problems on the test drive, even if you don't know much about cars.