U.S. Census Bureau:
The USGenWeb Census Project
The USGenWeb site, hosted by Rootsweb, a component of Ancestry.com, is "an all-volunteer project to transcribe census records in a standard format in order to make them available to genealogical researchers on the Internet." It is not directly associated with the Census Bureau or any facet of the U.S. federal government.
1930 Census Fast Facts. From The University at Buffalo (PDF)
See also General Information. From The U.S. National Archives and Records Administration (NARA).
See also Census guides at LUC (above) for this item in print.
1930 Census Fact Sheet. From the U.S. Census Bureau.
Census Bureau News: 1930 Census. From the U.S. Census Bureau.
Citing Records in the National Archives of the United States,
General Information leaflet No. 17. From NARA.
Clues in Census Records, 1850-1930. From NARA.
Measuring America: The Decennial Censuses From 1790 to 2000. From the U.S. Census Bureau.
Population and Housing Items on the General Census Schedules 1790-2000
Compiled by Grace York, University of Michigan Library, March 2002. Download requires Microsoft Excel.