This topic has also fascinated us for some time now. After studying the literature on the concept, we set out to find these sort of food production forests. We did find one gentleman here in West Seattle who has been maintaining one for several years. In addition, there will be a speaker at the upcoming West Seattle Edible Garden Fair on May 23rd who will be speaking directly to this topic. Check out the website at
http://gleanit.org/ for full details.
I have a feeling the books don't do this fascinating topic justice so I'm really looking forward to hearing this presentation.