Check out the interview that 7imp has up on Jack Gantos (this is for the Winter Blog Blast Tour).
He was a professor at Emerson College when I was there (although I never could get into his Children's Literature class!!) and I he is a truly gifted speaker as well as gifted writer. How can you not love Joey Pigza!
Also, if all you have read is his children's books, you need to go out RIGHT NOW and get Hole in My Life, his autobiography.