The editorials , if present , will be in the discussion forum or you might find a link given in the announcements on the contest page.
Even i am irritated by the fact that some contest problems aren’t added to the practice section.I think it is currently up to the contest organizers to decide whether to add problems to peer section or not.Dont know why some people choose not to upload problems. Hope it is made mandatory to add all problems from external contests conducted here.
Now coming to making editorials mandatory, I agree with you that it is important to write editorials for contests that are conducted but you must understand that writing editorials is a very challenging and tedious task. Infact Codechef pays the editorials of contests around $250 for writing editorials.
Since most of these contests are conducted by college students, it is very difficult for them to spend significant amount of time writing editorials.I had myself written a few editorials for our college contest and it proved to be very difficult and time consuming. Making editorials mandatory might dissuade a lot of people from conducting contests.
However i feel the organizers should(not must) provide a small guidelines ,even if it is just a few lines , after the contest detailing which algorithm/data structure was expected , a link to sample solutions and some pointers to solve the problem.