I was gonna say Battle.net/war3exp/
But that is pretty much what you DONT want. Well, basics is more of a playing thing. After reading a site, you beat some computer players. After you realize what everything does, and a sufficient build order. You then start RT or something. Then when you get better at say 3on3, reduce the players. Sooner or later, you may either 2on2 or Solo for th erest of your career.