Crab Apple Web Logs

I have seen a lot of ads for different companies that have a tefl course, and I am wondering whether one of these companies is better than the others. Can anyone tell me which course prepares you for the exam the best? I need to get some advice on how to take the test as well as some help figuring out what I should study the most. I don’t want to spend a lot of time studying something that isn’t going to be on the test if I can avoid it. I want to know what is usually included and what is not.