The podcast is called Angela Watson’s Truth for Teachers and it’s free for everyone. You can get the episodes here.
The MP3 version of The 40 Hour Teacher Workweek Club content is just for members. It’s the audio version of what’s in the PDF that’s sent each month, and each one is usually around 20-40 minutes long. The audio version of the club content can be found in each month's lessons. (You’ll see a PDF version for printing/downloading, and an MP3 version for listening).
(In case you're wondering what exactly a podcast is....a podcast has a "feed" which is automatically updated with new episodes and is free/open to the public. You can go to iTunes and subscribe to a podcast (like Truth for Teachers. There is no podcast for the club, just audio versions of the club content.)