TM-GT

Google is probably one of the best places to find tutorial on their own products. Most of their products are pretty intuitive, but as you ascertained from your Google Earth project, there are lots in details that bring out the best in the application.

Let's start here: http://services.google.com/apps/resources/overviews/welcome/topicWelcome/index.html

Now, let's visit this amazing wiki: http://googletools.barrow.wikispaces.net/