Looking for official publications of the United States Government? The best place to start may be with one of the Government Printing Office's (GPO) two main searching tools: FDsys and Catalog of U.S. Government Publications.
FDsys contains documents from about 50 collections of Government information ranging from Congressional materials, to Presidential materials, to judicial materials, and materials from Federal agencies. Many of these are foundational to the operation of our government. For a full list of FDsys collections visit http://www.gpo.gov/fdsys/browse/collectiontab.action.
All of the documents in FDsys are available online. They are either born digital or have been scanned to PDF format.
The CGP contains over 500,000 records describing federal publications from all three branches of the Federal Government. These records cover both historical and current publications. These publications cover a wide range of subjects and include studies, technical reports, handbooks, fact sheets, and so on.
For those titles which are available online, a direct link is provided. For those titles available only in tangible formats (e.g. paper), the CGP provides the ability to search for depository libraries which hold the title. The LRC staff is happy to assist you with obtaining access to any of these materials.