I recommend reading some books on shaders, like shaderX 2 and the like, or if you're broke like I am at the moment, just search on google for shaders.. Off course this is only for general info on shaders, for using it in A6 it's best to try some of the wiki shaders, download the Surreal shader editor from Nadester and search the forums... Just to show some of the things I've done to find some info on shaders..

Cheeers