Demo Tutorials:

Here are a few references for your photoshop paintings:
Class Demo:

On painting black and white to color:

On the painting process from line to color, it's similar to the demo but straight to color instead of black and white:

By my friend Ahmed Aldoori part 2 and 3 of a full character process:
BW Process:
https://vimeo.com/42114005

Painting the face:
https://vimeo.com/42961835

Overall color:
https://vimeo.com/43104283

Good luck!