You may find the perfect data for you map, but it is in shape file format. You can use ArcGIS to convert your data into KML format for use in Google Earth.
1. Save your spreadsheet as a .csv
2. open in Maps Engine
3. Select your location elements
4. Seclect your fileds to display
5. Save as kml
6. Open kml in Google Earth
You can create a spreadsheet online and bring it into google earth.