General Clearinghouse for Sites with City and Region Information:
Tufts Geodata Portal
Try searching for a specific city
MIT – GIS – Find Data – their listings of GIS Data by State
Includes many county and city GIS data sites as well.
University of Arkansas – Geospatial and Attribute Data Listing
An excellent site for getting access to US state clearinghouses and other agencies serving geopatial data (also includes US Federal and international data).
California
San Diego, CA – SanGIS
Good download access and good metadata to a wealth of urban/metropolitan/environmental GIS data – provided by the City of San Diego, the county of San Diego, and the San Diego Association of Governments (SANDAG). You need to register first, but it is free.
San Diego – San Diego Association of Governments
There are a few GIS data sets here not easily found on the SanGIS site, including land use.
Note: additional data can be downloaded from the Bay Area’s Metropolitan Transportation Commission’s Maps and Data section
Connecticut
CLEAR (Center for Land Use Education and Research)
University of Connecticut – good site with both land use research project information and GIS data downloads, mostly focusing on Connecticut, including a number of coastal zone/riparian research projects.
Connecticut Department of Environmental Protection
GIS Data Download Site
Connecticut GIS User to User Network
Good GIS community site for Connecticut organizations using GIS
Louisiana
City of New Orleans GIS
Includes damage assessment and permits for reconstruction from Hurricane Katrina
Greater New Orleans Community Data Center
A non-profit that focuses on providing data for non-profits
Lousisiana GIS Council
Boston Metropolitan Area – Metro Boston Data Commons
New (2007) site from the Metropolitan Area Planning Council (MAPC) and the Boston Indicators Project. Includes a variety of socio-economic and other data regarding 101 cities and towns in Eastern Massachusetts. The main tool is an online mapper, but it also has tools to extract GIS shape files and Excel tables.
Oregon
Portland Metro Data Resource Center
Metro, a regional government, maintains an extensive GIS database with information concerning the Portland metropolitan area. For the most part it is not downloadable for free, but it has good documenation, online viewing, and is an excellent example of a well-organized metropolitan GIS. Also note that students may purchase a CD of the RLIS main data set for $65.
Texas
Texas Natural Resources Information System (TNRIS)
Texas state GIS data clearinghouse, includes Border Information Center
Austin
- Capital Area Council of Governments (CAPCOG): downloadable, well-organized data for the Austin Metropolitan Region
Houston
Rice University – GIS Data for Houston: this site from Rice keeps track of where to find Houston data, most of which is either available for free download or at very low cost.
Washington, DC
District of Columbia Geographic Information System
A wealth of free dowloadable GIS data layers (ESRI shape file format), very well documented. Go to the GIS Data Search link – the search tool is a bit clunky, but you can also browse by alphabet letter.