I debated posting this to the neanderthals, but decided here would be better. I generally prefer power tools when I can, but like anyone, have to clean some stuff up with chisels here and there. Anyway, the older ones I have are pretty well dull beyond use and the newer ones are close. I haven't used them much, and have never sharpened them. (yeah, I'm that green). So, what is the cheapest stone or stones I can get away with. I stopped by woodcraft, and was dumbfounded by the options (and the prices). how do I know what I'm looking at, or what I need?