Literature -- Tutorials, books, and documentation
Thuban -- GIS system for Windows and Linux
MathWorks -- Lots of tutorials for developing mapping systems
Wikipedia -- Wikipedia reference
FreeGIS -- Free GIS resources
GRASS -- The standard GIS for Linux
GISCafe -- Magazine
LandSerf -- Terrain modelling
Geographic Information System is a name for many types of data-processing tools, which are optimised for mapping information. Applications range from city planning to surveying to geographic modelling and science. These tools can even be used for your mathematical data plotting.
For more on terrain-generation, see the simulations area
