The Hand Cut Dovetail Site has links to How-To resources including online articles, books, and videos. He's also added links to related tools including dovetail saws, chisels, mallets, and marking gauges.
If you like power tools more than time-honored craft, you can consider getting a dovetail jig for use with a hand-held router. I admit it...I have one.
Anyone wanting to learn more about cutting dovetails by hand should check out The Hand Cut Dovetail Site