Do you know what green companies are in your area? As I have mentioned in the past, Green Career Central contains some great tips, but their post on maps has to be one of their best.
One of their links, Clean Tech Startups, is a google map which shows where various clean tech startups are around the world. It not only shows you who and where each company is, but it differentiates them by industry.
Green Career Central also links to the Environmental Defense Fund’s maps of renewable energy and energy efficiency companies in manufacturing states.