Familiarity with the institutions that collect and publish statistical data can often aid your search. In general, there are four major sources of social statistics.

• Government Statistics: National governments are often the only institutions with the resources (and authority) to collect comprehensive social statistics, and thus publish the overwhelming majority of social statistics available. Most countries have a national statistical agency that collects and publishes statistics, and simply perusing that agency's website or publications catalog is often the best way to find their statistics. The US is more complicated, since responsibility for statistics is spread among many federal agencies. Wikipedia has a list of the principal federal statistical agencies. The United Nations and other international government organizations collate and publish comparative statistical data from their member nations. Most state, provincial, and municipal governments also collect and publish some statistics.
• Public Opinion Polls: News and political organizations routinely conduct or commission opinion polls on a variety of topics. Many of those poll results can be found at the ICPSR.
• Academic Research: Social science researchers often gather data as part of their studies. The results are usually presented in the published academic literature. Search any of the major article databases to find these articles. Most articles will only contain summary data, but the complete data sets can often be obtained from the original researchers.
• Commercial Market and Business Research: Many corporations and trade organizations collect economic statistics and sell them for profit. Often a very hefty profit, which means Cal State East Bay has limited availability of these types of products.

Governments provide such a preponderance of social statistics, that it's often important to remember that there are certain types of data you won't find in government statistics, at least in the United States. Some common examples to watch out for:

• Religion: Some older censuses (19th century) asked religious affiliation, and you can sometimes find statistics on numbers of churches. Other than that you’ll need to rely on non-government sources.
• Voting: The United States employs a secret ballot. The federal and state governments have statistics on what votes were cast (by precinct, county, or state), plus demographic statistics about registered voters, but nothing that links the two. Exit polls are generally the only source for voting statistics by race, age, sex, or other factors.
• Detailed Household Expenditures: The government tracks how much families spend on big categories like food, rent, and entertainment, but they don’t track how much families spend on meat, curtains, home videos, or individual brand names. Use commercial market research reports for detailed spending data.
• Product Sales: Unless it crosses the border (see US Foreign Trade), the government rarely keeps records on the manufacture, transport, or sale of individual products. Some statistics are available for primary resource production (agriculture, fisheries, forestry, and mines) and sales by industry. Otherwise, use commercial market research reports for detailed sales data.
• Microdata: Though governments collect vast amounts of data, because of privacy laws most of it is published only as aggregate data, i.e. summary tables which don’t reveal anything about the individual people or businesses. The major exceptions are SEC reports for publicly traded companies, campaign finance reports, the Census Public Use Microdata Samples (PUMS), and the census schedules (the original forms released seventy-two years after the census is over).