Global Mapper Software designs, develops, and distributes the Global Mapper software package that is also distributed by the United State Geological Survey under the name dlgv32 Pro. Global Mapper is more than just a utility; it has built in functionality for distance and area calculations, raster blending, feathering, spectral analysis and contrast adjustment, elevation querying, line of sight calculations, cua-ans-fill volume calculations, as well as advance capabilities like image rectification, contour generation from surface data, view shed analysis from surface data, terrain layer comparison, and triangulation and gridding of 3D point data.
You can downloaded for a free trial, or purchase it online. The website also provides a user manual, and Global Mapper forum. By joining the affiliate program you are able to sell Global Mapper licenses at the suggested retail price; by doing that you will get a 30% commission on every sale. You can sign up in the website and start earning some extra cash. 
