For the US; there is a fairly comprehensive collection geographic data sets available from the National Atlas http://www.nationalatlas.gov/atlasftp-1m.html http

For the US; there is a fairly comprehensive collection geographic data sets available from the National Atlas http://www.nationalatlas.gov/atlasftp-1m.html http://www.nationalatlas.gov/atlasftp-1m.html all freely available and public domain. And of course the US Census http://www.census.gov/geo/maps-data/data/tiger.html http://www.census.gov/geo/maps-data/data/tiger.html TIGER/Line dataset. The World Bank http://maps.worldbank.org/ http://maps.worldbank.org/ has maps covering multiple economic indicators, coverage is uneven and it's mostly focused on the global south. http://geocommons.com/ http://geocommons.com/ has a largish assortment of geodata but the curation and search functionality is a bit confusing and they require a login. http://www.statsilk.com/maps/download-free-shapefile-maps http://www.statsilk.com/maps/download-free-shapefile-maps has a number of pointers to other resources.