Somewhere, a long time ago, I found some programs that you could pay for. For now, I suppose you just have to use shortcut guides. I'll keep looking... Here's some for now, but I'll find some better ones.
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After some digging around in my pocket, I found this article: http://goo.gl/9qeSxZ. In here, you'll find Key Rocket as Lifehacker's favorite choice. It's $135/year though. I think that's really expensive, but there's an evaluation copy. Shortcutfoo is an online program that helps you master them, but it doesn't install on your computer. From a quick observation, it looks like an awesome version of flashcard training. Hope this all helps!
*Removed Gmail Guide: Superuser won't let me post more than 2 links until I have 10+ reputation.