Scripting in GS really isn't difficult, it just takes much practice. I recommend learning Javascript up to your limit first, then acknowledging how Java interacts with GS. Here's a site that I find very easy and well-made to learn Java: http://www.codecademy.com/

After you've reached your limit of choice, go ahead and read this article, created by FowlPlay4: http://public.zodiacdev.com/Fowlplay4

This is of course, if you'd like to get into scripting.
Leveling on the other hand, is very simple, but a good level will take a ridiculous amount of effort and skill.