On this past Monday, Apr. 2, the US Census made the source documents (on film) of the 1940 census available via this site, http://1940census.archives.gov/. While the servers immediately crashed shortly after public access was enabled, the site is typically available now.

This is the page from the census pages for the Winchendon MA downtown area that lists my father and his parents (see lines 15-16); the partial detail of these lines is image no. 2. The third image is the detail of the listing for Sherry’s dad (Lewis A.) and family from the census pages for Thomaston, Maine.

The key to locating specific people in these records is knowledge of the subject’s residence address in April 1940. But that is just the start. After accessing the site and getting to the listing for the community in question, you will need to identify what “Enumerator district” contains the address you are seeking (the site provides a map showing what district covers what area of the community). Then you need to scroll through as many as 35 pages of the hand-written listings.