An excellent article was written at mym.com which can help new gamers and help those "in-between" gamers having trouble getting passed a plateau in their game.
The article explains great ideas and concepts about training to get better in a RTS (particularly WarCraft 3 but this article can be used by StarCraft gamers also). The in-depth explanation is enough to get the brain running for training and understanding the game(s) more. There is some words of wisdom from some pro players near the end of the article as well.
Excerpts:
Check it out and I'm sure it will help you figure out the simple problems in your game (or if your lucky you'll figure out the big problems).
Links
meetyourmakers.com - Main Article