One day, I said to myself, "hey, I want to learn how to sharpen blades." I purchased this book, and learned that one doesn't merely decide that he would like to sharpen blades. I now respect the craftsmanship of an expert blade sharpener. I may still take some baby steps - at least acquiring the capability to do the rough sharpening of garden tools, my principle goal anyway - but we'll see if it makes sense for me to take it further.
Amazingly comprehensive book -- if you're a woodworker. He has a whole section of electron microscope pictures of the results of different sharpening techniques, and goes through just about every woodworking tool that has ever existed, talking about how each is used and how sharpening it should be approached. He talks about the difference between oilstones and waterstones, micro-bevels, sharpening fixtures, wet and dry grinding, how to regrind screwdrivers so they work right, how to set up competition two-man saws: it's amazing. He's also a funny writer, not in the jokey way but in clever, wry asides about how things go wrong and why he believes things, sometimes in the face of all evidence to the contrary.
This is one of the two sharpening texts that I've seen recommended. I've skimmed this one, and it appears both thorough and technical. The reviews on Amazon favored this text over Taunton's Complete Illustrated Guide to Sharpening.
Excellent and comprehensive. Covers the full process from grinding a new blade through to final sharpening. Includes coverage of a wide range of stones and abrasives, and some great ideas for difficult jobs like honing gouges. Also covers scrapers and misc edged tools.