Here is a easy free way to have a topographical map on Google Earth.  Make sure you have Google Earth installed.  Open this link: http://services.arcgisonline.com/arcgis/rest/services/World_Topo_Map/MapServer Click on the Google Earth tab at the top of the page. It should start downloading. Drag the downloaded file straight into the open Google Earth window. It will take a few seconds and then render a topographical map on Google Earth that can be viewed at any distance.   Have fun!