If you are interested in getting to know more about Permaculture here is a .pdf document by Permaculture Founder Bill Mollison. This is pamphlet #I in the Permaculture Design Course Series published by Yankee Permaculture & the Barking Frogs Permaculture Center who are publishers of Permaculture Publications.

http://www.bettertimesinfo.org/pdc_all.pdf