I found this video (long) very interesting and useful http://www.youtube.com/watch?v=up3Z7LU2pV8 http://www.youtube.com/watch?v=up3Z7LU2pV8 Also, check out all

I found this video (long) very interesting and useful http://www.youtube.com/watch?v=up3Z7LU2pV8 http://www.youtube.com/watch?v=up3Z7LU2pV8 Also, check out all videos and books by Bruce Blitz For example - http://www.amazon.com/dp/0762402490/ http://www.amazon.com/dp/0762402490/ Watch his videos on youtube first, to get an idea of his teaching style Disclaimer: I'm not an artist, just someone who has interest in this topic.