I live in BC, Canada, and am publishing a book about a Canadian spiritual teacher. I would like to include a transcript of an audio cassette from one of the teacher's meetings. The tape was available for sale and is now available as a CD. Do I need permission?
I'm sorry, auteur. FreeAdvice addresses US legal questions and US law concerns only. You will need to find legal assistance in Canada.
However, based strictly on what you have said (while acknowledging that there are differences between the laws in the US and Canada), the answer would be yes - with a few exceptions.
You generally need permission from the holder of a copyright to publish their copyrighted work. And, in the US, there can also be a concern with publicity and privacy rights.
For the specifics of your use and the cassette in question, you should find an attorney in your area.