If you are in the new and exciting field of ‘green’ buildings, then you are most certainly familiar with the LEED certification system.  LEED, which stands for Leadership in Energy and Environmental Design is a third party certification program for buildings and structures.  Those who work in this area must pass a certification exam, and it is hard.  Most who pass it have taken a LEED exam prep course to brush up before taking the test.  I found some really great web sites at hotfrog.com, which is a Web based business directory that is just chock full of great links and sites.