When I got started in the hobby the mp3 audio course helped me quite a bit and fit into my commute nicely. This was circa 2011 and I still have the files (40 files in total).
Now I have a friend in a similar situation and I think he would also benefit from the audio course -- iirc most of it was timeless content.
What's the current state of the audio course? Is it available for him to purchase? If not, has it been placed in the public domain so I can give him a copy of mine?
So far my own searching has turned up ebooks, but no audio course.