What post-secondary institutions offers courses in sound technician?

Your best bet when seeking specific programs like this is to break it down: search for the specific keywords (in this case “sound”), and consider synonyms, too, like “audio” and “recording” to ensure you find as many relevant results as possible. Here’s a quick search to help you get started: https://www.schoolfinder.com/Programs/ProgramSearchResult.aspx?searchWord=sound&programCategory=-1