The 1926 Canadian Census of the Prairie Provinces (including Alberta, Manitoba and Saskatchewan) has been released to the public.
I can’t find some relatives and their neighbours south of Tompkins.
Are all the records transcribed?
If you go to the Census of the Prairie Provinces, 1926 at the Library and Archives Canada site, in the left hand menu is "Districts and sub-districts". Click on that, then on Saskatchewan,and you'll get a list that you can search in your browser.
Look for "Tompkins" and you'll see that in District 24 - Maple Creek, Sub-District 67 is the village of Tompkins, and Sub-District 66 is the Township around Tompkins.
Now you can go to the 1926 Census Search Page, Show the Advanced Search Options, enter Saskatchewan as the Province, 24 as the District number, and 66 as the Sub-District number.
Click on "Search" and you'll get a listing of the approximately 300 entries for that district that you can look through individually for your relatives and their neighbors. Look for strange spellings that might be them. Names were often written the way the recorder heard them and guessed they might be spelled.
If you don't find them, then use a detailed map of Saskatchewan that shows the Townships, Districts and Sub-Districts and identify adjacent Townships and Ranges to those in Sub-District 66:
Since your Sub-District 66 is made up of Township 13 in Ranges 20 and 21, you can see from the map that adjacent sections would be:
Then go back to the Districts and Sub-Districts list and find out what Sub-Districts those adjacent township/ranges correspond to. You can then look through the records for those Sub-Districts. This will be the best you can do to find your relatives and their neighbors and hopefully you will find them reasonably quickly.
You can use wildcards in the name search and include part of a surname or a first name followed by a star to narrow down the results and catch misspellings, e.g.: Lou*
I was able to find my father's step father, Louis Kessler this way. His name was spelled as Louie Kasler.
I'm assuming that you mean the Canadian Prairie Census of 1926.
As far as I know, there are multiple transcription efforts.
To answer your question "Are all the records transcribed?", you need to be more specific about which effort you are referring to (and I have no inside information on any of the ones that I listed).