ESRI

Environmental Systems Research Institute or ESRI, is the leading GIS software company in the world.  It was the software I used to make my maps.  The company has different types of software depending on what type of mapping needs to be done.  The types of software range from a free software which has limiting mapping capabilities, to their high-end Arc/INFO which uses command line to change, add, or manipulate geographic data.  Check out their website, as it has lots of information about GIS including maps and a mapping service.