The 1940 anticipation is really building. I've seen estimates of about six months to get the name index of the 1940 census available. If you just can't wait in the meantime, and if you have an idea where your ancestors were living, then you need to find the enumeration district number that was applied to their neighborhood or village. And that means it's time to visit the indispensable Stephen P. Morse and his one-step pages.
He's got a great set of pages up with step-by-step guidance for finding your ED number based on your ancestor living in a rural area, town, or a major city. The tutorial is here:
And the Unified 1940 Census ED Finder is here:
My boring Scandinavians in Chicago never moved, so I should be able to find them right away. My husband's Kansas/Oklahoma/Texas relatives will have to wait for the name index, I think.