This site "Community Media Database", http://communitymediadatabase.org, created by Rob McCausland shows the amazing distribution of access tv, broadcast tv, and low power FM stations.
When you go to the site, you can pan to a particular state or click on its abbreviation in the list below the map and you can zoom in using the zoom bar. Using the drop down menus at the top, you can drill down into the Spreadsheet Directory showing the various google docs with even more detailed info if you register.
Rob has the full support of the Alliance for Community Media. If you don’t see your station listed or you want to correct something, you can contact Rob at: firstname.lastname@example.org.
Also, anyone doing congressional candidate interviews or debates in this political season, please see congressional coverage button in the maps' top right, and email Rob (email@example.com) your coverage data for inclusion.
Thanks to Rob McCausland for this great visualization which should be very useful to producers as well as stations!