A sister topic for the drawing topic, the resource one. There is one for Photoshop, but here I want to focus on the learning process, as I'm pretty sure some people would like to learn.
As for now, I have written a guide. It's a side project I had in mind when I started learning, that is, to write down my own experience in hope that it will be useful for others. It's an eternal work in progress. ( 8000 words at the moment ). There is also a number of link inside to more resources xD.How to CG
You may want to suggest things, post your own guide here, or other resource from the Internet.