Like everyone else, I was looking forward to browsing the newly-released 1940 US census today.
Because the census is not yet indexed, the only way to find your family now is by finding the census enumeration district (ED) and then browsing all the pages of the ED. To find the enumeration district (ED), you must first know the address - the complete address - not just the street. At least that is the case for my family who resided in a big city.
I went to Steve Morse's excellent ED finder and followed the directions by filling in my great-grandparent's exact address. With the ED finder, I was able to zoom in to the exact city block by adding cross streets. It was really very simple. However, when I clicked on the ED, I received an error message at the NARA site. No surprise that the National Archives site is overwhelmed. Hours later, it is still telling me that it is "preparing image". I can see there are 34 pages of this ED for me to browse if I only I could get the images to load. No word when this issue will be fixed.
So I went to Ancestry.com who is also offering the 1940 census for free. Ancestry is in the process of uploading all of the census records and indexing them, They have a number of states done, but not the states where my family lived. Ancestry does have a sign-up and they let you know when the state you are interested in is completed. The 1940 census will be free at Ancestry and I had no problem loading the available census here.
While at the Ancestry site, I noticed that they have their 1940 Era Records for FREE through April 10. This includes, surprisingly, the 1930 census, and many city directories that can help find the exact address needed to find the ED to enable browsing of the census. So, I think I will spend my time collecting exact addresses from the free 1940 Era Records at Ancestry.com until I can actually view the census images.