There is a lot of information on sustainable architecture to be found on both the internet and in various books and magazines. It feels like I've seen most of what's out there while researching for my March dissertation. www.sustainia.me is one of the best sites I've found so far. It's comprehensive, but it also gives the reader a good overview and understanding of the issues and possible solutions without complicating it too much. Click on this blog post title, it takes you straight to the Sustainable Checklist for Buildings - the checklist every architect should follow!
While we're on the subject.. The Environmental Design Handbook by Sofie Pelsmaker is THE number one book on environmental design for architects. It's a great introduction if you don't know much about the subject, and brings you further into the depths and details on sustainable design as you get more advanced.