There are guides to materials online, as well as in the Columbia University Libraries, in the following areas:

• Major Databases
• Google Advanced Search
  Use the popular Google search engine to perform searches that will retrieve items only  from official U.S. federal, state, and local government web sites. In the last search box, type .gov or .mil to restrict your search to those domain names.
• Mobile Apps
  Dozens of apps from the Federal government: GAO, Marines Magazine, Congressional Record, EPA AirNow, House & Senate Member Guide, National Weather Service, etc.
• Citing Government Documents
• News: Government & Politics