Links to boundary files (county, state, roads, etc)

Here are some links to sites that have GIS files that can be used on EDX software. These files may include county boundaries, roads, streets and other type of GIS information. 

US Census Bureau Census 2000 County and County Equivalent Areas in ArcView Shapefile (.shp) format – 
National Atlas Data Download – 
US Census Bureau TIGER/Line® Shapefiles and TIGER/Line® Files – 
2010 Counties FTP link (has 2010 county boundaries by state or combined, and 2012 counties combined) – 
StatSilk – a site containing links to other site containing free shapefile maps: