I haven’t been able to access any images at the “official” site (1940census.archive.gov). Needless to say it has been overloaded with people trying to access all of the states. Ancestry.com has done a great job of putting states on-line rapidly (for free I might add). I am bit disappointed that thus far the only southern state uploaded at Ancestry.com is Virginia. I was able to search Indiana and Pennsylvania on my husband’s line though.
Family Tree Magazine has a good article with links to several resources to get “up to speed” on the 1940 census.
President, Birmingham Genealogical Society