GIS Tools
Google Earth
Google Earth allows users to import and view their own data, using Google Earth imagery as a backdrop.
Download Google Earth here.
QGIS
QGIS is a free and opens source GIS software that allows you to create, edit, visualize, analyze and publish geospatial information.
Download QGIS here.
R
R is a programming language/ system of free software services for data manipulation, calculation and graphical display.
Download R here.