Here's a question for you

[Karro]

"This sounds like a job for the Masked Layer!!!" (cue cheezy superhero music and echoes)

Seriously, if you want to break up a drawing into different "sections", the best way is to use Layer masks. There is a great Tutorial by (correct me if I am wrong folks) jfrazierjr on the subject even if it isn't for gimp. RobA's tut also goes into the use of layer masks quite a bit, and I can not recomend that tut forcefully enough.

I think you are wrong, but only half-so. The layer-mask tut was made by jfrazierjr. But it actually is for GIMP.

It's a really great tut for newbies and beginners; it breaks things down pretty simply, I think. [note: I'm not much better than a newbie/beginner myself; I'm still learning tons of new things, but I think I had the layer-mask thing down pretty pat by the time of this tut.]