There is a Sepp Holzer article in Permaculture Magazine, No 67 Spring 2011 that is just a good summary of his use of terracing in permaculture and creating microclimates in doing so.
www.thehappypermaculturalist.wordpress.com
Wait for it ... wait .... wait .... NOW! Pafiffle! A perfect tiny ad!
It's a bit like "run away to the circus" but for gardeners