I am using photoshop cs5 and everything i know i learned by myself starting with a Fire text effect photoshop cs2 tutorial.
I've watched a fucktons of tutorials and i can fairly say i have Medium knowledge in photoshoping and Advanced in making avvys.
Still i have no ideea how they make the realistic effects on some of the avvatars / sigpics.
Still i dont think i am able to give you a tutorial.