You can test the Mozilla Location Service with Firefox on your desktop by changing your "geo.wifi.uri" about:config pref to:

  https://location.services.mozilla.com/v1/geolocate?key=test

Then try using a geolocation service like Google Maps or http://html5demos.com/geo . If it can't find your location, check Mozilla's zoomable coverage map to see if your neighborhood is covered: https://location.services.mozilla.com/map . If not, please consider installing Mozilla Stumbler to help map it. :)