The Internet is chock full of information on being all the green that you can be. Here is just a sampling of the sites where you can find more information.
EcoLogo Program, www.ecologo.org
Green Seal, www.greenseal.org
Scientific Certification Systems, www.scscertified.com
Daylighting Collaborative, www.daylighting.org
Environmental Protection Agency, www.epa.gov
Whole Building Design Guide, www.wbdg.org