We love Robin Grille. He has a new book out called 'Heart to heart parenting'.
I find some of the others mentioned are more to do with sleep issues while this one is a generally parenting book so I guess it depends on what you are after.
Robin Grille is an Aus psychologist and this book is very readable but still based on current research. We would call ourselves gentle parenters and it fits in with our parenting styles and really helps us understand what is happening so we can make our own decisions on the best course of action.