Since you got high bandwidth try here. All I can add to what he said is when you are holding your pick only leave a tiny amount of pick out and kind of (for lack of a better word)"roll" your thumb into the string slightly right after hitting it with the pick. Use vibrato to gain more effect. He is definatly right about the sweet spots. The spot you should pick the string at changes between different frets and different strings and every guitar and setup can have different sweet spots. You gotta find them on your guitar setup. This is a common problem.