Thanks for the info. I use an OpenStreetMap application called JOSM for this. It allows you to load all of the Gov't data as WMS layers, which load much faster and smoother than the KML layers in Google Earth, and the program doesn't need much in the way of computing power to run. It doesn't have 3D terrain, but you can load the OpenCycleMap topo map to get an idea of terrain. Best part is, if something is missing in OpenStreetMap, you can just add it and it will show up within a couple days.