http://www.texasrealtors.com/mr/pubs/magazine/issues/2012/0512/Green.pdf This article from the May 2012 issue of Texas Realtor helps to explain 'Green', not as in the color. Very helpful & informative article.
http://www.ftc.gov/os/2012/10/greenguidessummary.pdf is a summary of the new Green guides from the Federal Trade Commission (FTC). The Green Guides is a recently finallized resource created for marketers to help them avoid making false environmental claims regarding their products/services.
It might be a good idea to familiarize yourself with these 2 helpful resources before shopping for your next 'Green' purchase.