First off, thanks for the great compliment, and now, on with the lesson.
Unfortunatly, no, I dont really use much in the way of RESOURCES, I've picked up the odd book and DVD over the years but always found they either tell me stuff i know or seem to miss out a key section of the images development. Mainly, the things that have helped me the most are my friends and collegues, they'll point something out and say, maybe try this etc, and that helps, so get other artists to CRIT your work. Something thats a bit tough on DA is finding people that have the nuts to say, 'yeah it's good but have u tried this?'
The next thing I do is look at other peoples work and REALLY look, beyond the WOW THATS GREAT stage, try and see what they have done, see if you can find early pics of the work, I find seeing how people START a picture can be hugelly helpful.
DONTS!
Dont get stuck on technology, there is no brush, or programme that will acheive a better picture than sweat and skill, remember Sistine Chapel was painted with a brush and paint.
DO
KEEP DRAWING, every day draw draw draw and draw, its how you'll get good, after that it's all technoque, if you can draw, you can learn the rest of it.
Hope that was helpful and not crap