Janine M. Benyus.  Biomimicry: Innovation inspired by nature. 

Thomas L. Friedman. Hot, flat and crowded: Why we need a green revolution--and how it came to renew America.

Kelly Lerner et al. Natural remodeling for the not-so-green house: bringing your home into harmony with nature. 

Barry Lopez. Helping Nature Heal.

William McDonough et al. Cradle to cradle: Remaking the way we make things.

Michael Pollan. The omnivore's dilemma: A natural history of four meals.

Paul Roberts. The End of food.

Paul Roberts. The End of oil. 

David T. Suzuki, et al. The sacred balance: rediscovering our place in nature.   

David T. Suzuki, et al.  The big picture.

(Suzuki has written over 40 books.  These are just two.....The big picture is recent, and The sacred balance is, in his own words, "my favorite.")