A fellow steel blogger maintains a web site of steel information here. It’s quite useful. Check it out. He calls it the most complete guide to hot and cold rolled steel strip on the internet . And it certainly seems quite complete. Lots of good articles on how it’s made, and so forth.
It is, however, somewhat Euro-centric. When you go looking for service centers, for example, you find lots in Europe, some in the United States, and none in Canada. But you probably know who your local service centers are. I find the European equivalent of SAE1050 (or whatever) is the most useful part.
Oh, and did I mention the price? It’s free!