The U.S. Census Bureau website (Census.gov) offers useful information related to business and industry.
For data on retail sales, click on the link for Economic Indicators and look for the link to Advance Monthly Sales for Retail Trade and Food Services.
Another web page (http://www.census.gov/econ/retail.html) provides links to other retail trade data from the U.S. Census Bureau.
The U.S. Census Bureau's American Factfinder website is a good source of Economic Census data for 1997, 2002, 2007 and 2012. The Economic Census comes out every five years. It is the U.S. Government's official five-year measure of American business and the economy.
In October through December 2012, forms were sent out to nearly four million businesses. Respondents were asked to provide a range of operational and performance data for their companies.
The 2012 Economic Census data has been released. To obtain the data available, click 2012.
Check out the 2012 Economic Census releases by state. Choose a state and then Retail Trade. The NAICS code for department stores. is 452111.