The organization Interaction, an alliance of U.S.-based international nongovernmental organizations (NGOs), has worked with a number of other groups including the U.S. Chamber of Commerce, to create a detailed interactive map of NGOs in Haiti (go to link, below is just a screen grab):

The site can be browsed by location, sector, organization or project and features maps highlighting NGOs’ work on specific issues, such as the cholera outbreak.
The goal of such a map is to increase transparency, facilitate partnerships and improve coordination among those working in Haiti. Using data gathered from the field, this site will also help NGOs, donors and the public make more informed decisions about where to direct their resources.
Haiti Aid Map is part of NGO Aid Map, a broader mapping initiative to provide detailed information on the work of InterAction members around the world.