the ASU Library has a wealth of information on Sustainability. Graduate students often need the expertise of a Subject Librarian. While Rene Tanner and Jenny Mueller-Alexander are the "official" sustainability librarians, you may need, and should feel free to consult, any of the librarians who specialize in your area of focus.
Each of the Subject Librarians has created Library Guides for their specific subjects. Some popular ones for sustainability:
Other Library Guides of interest: