Actually, I would recommend Howto JCS over JCSref if you're looking for a tutorial. JCSref is more advanced, and it's a collection of unrelated articles with no real narrative flow, whereas Howto JCS is aimed at covering all the basics and getting you out the door with the tools to make a solid level. JCSref does have a good list of hotkeys, which I think maybe Howto JCS doesn't, but you can find those in the JCS help file as well.