"Tool Steel Simplified" by the Carpenter Steel Co. will give you a pretty good feel for the differences between O-1, W-1, S-7, etc. The book doesn't use those names -- it uses the Carpenter Steel brand names, and you have to deduce what is probably comparable -- but it's still pretty good. You'll have to find it used, but there are copies floating around.
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Try to make a living, not a killing. -- Utah Phillips
Don't believe everything you know. -- Bumper sticker
Everybody is ignorant, only on different subjects. -- Will Rogers
Law of Logical Argument - Anything is possible if you don't know what you are talking about.