Q. How do I find U.S. government statistics?

Census (and related survey) data from recent decades:

American FactFinder

Census data through American history:

Census of Population and Housing

Census data about individuals (accessible 72 years after each Census):

Western Libraries Population Schedules page

Data sets (open access) compiled by the federal government:

Data.gov 

Economic statistics from around the world:

FRED: Federal Reserve Economic Database

The government's summary of important data about life in the U.S., 1878-2012:

Statistical Abstracts

Historic Statistics:

Millennial Edition (commercially Published)

Earlier editions in paper: OneSearch results