Although I've heard there are still some issues with the Monterey Bay Aquarium's Seafood Watch guide, it is still a step in the right direction, and following their recommendations can help you lessen your impact on fish stocks. There are several viewing modes available here:
http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_recommendations.aspx?c=ln
Video from: http://www.youtube.com/watch?v=F6nwZUkBeas