The Green Restaurant Association (GRA) is a national, non-profit group that provides the official Certified Green Restaurant mark. It has been working with the restaurant industry since 1990 to help each restaurant measure its environmental accomplishments through various categories such as water efficiency, waste reduction, recycling, sustainable building materials, sustainable foods, energy use, preferable disposables, and pollution reduction.
GRA is active in 41 states and Canada. You can search for green restaurants in your area on their website.