In this guide, census information is broken into two discrete categories: population statistics, and the manuscript census. "Population statistics" are numbers describing various characteristics of the population, and are available through a variety of free and library subscription resources. "Manuscript census" refers to the actual forms on which the census information was recorded, with precise information on individual citizens and households. They are kept confidential for 72 years after their recording, at which point the Census Bureau makes them available to the public.
To get to know the census better, explore IPUMS' collection of digitized published census volumes. It's a great way to track major changes on many issues in the U.S. over time, and you'll be surprised what you can find!
Important - American Fact Finder will be taken offline on March 31, 2020. Census.data.gov has taken over as the primary data portal for the U.S. Census
Government Information is a regional library of the Federal Depository Library Program as well as a depository of Colorado state, United Nations, and European Union information. It consists of over five million items from the United States government, Colorado and other state governments, foreign governments, and international governmental organizations like the UN. As a federal depository, the Library also offers assistance and its collections to members of the public. This includes providing public computers for unrestricted access to government information on the Internet.
Information is arranged by government entity or agency. The agency is the best place to start.