Social Security Admin. This will tell you what names have been most popular over the years. You can donload it into a spreadsheet very easily. A little difficult to use at first - extract and download labor stats to spreadsheet US Census Population Estimates You can download updated population estimates by state, city, MSA or county. You have to do a little cutting and pasting but it works okay.
Record layouts are also on the page.
Health and Human Services list of excluded doctors On this site you can download a self extracting file that has a list of all doctors and organizations excluded from doing business with the government. On time statistics for airlines by airport and other variables. National Cancer Institute Atlas of Cancer. The site has a good mapping tool as well. This database is not downloadable but can be searched by company name.