There is a standard elevation format known as Digital Elevation Model (DEM) . If you go to
Digital Grove you can find links to all sorts of free, share, and commercial apps for this purpose.
I've played with this a bit. One app, 3DEM is simple and free, but of course limited. I like the idea of a 3D terrain model (especially in hilly areas like up north, eh Thorn?) showing all the NS results.