"Dark art" tutorials for photoshop and other programs?

well there arent really any tutorials. I suggest you learn photoshop from a 'whole' rather than simply learning 'dark stuff' because at some point or another you will need to use all the tools and by understanding it as a whole, you will understand what to do when doing 'dark art'. Luckily, I had to take photoshop course during my animation program. But I find that the program 'Combustion' is alot better than photoshop and has better tools. You can render images alot better and when wanting to do 'dark themed' stuff, Combustion is the way to go.