You can buy some of the videos as ebooks with full text (the text you see at the bottom of the videos). I also have an R tutorial. Most ebooks consist of 80-100 pages and are in the form of plain PDF documents. Currently, I use the Payhip platform to sell ebooks. To buy an ebook, go to:
Note that not all videos have a corresponding ebook yet.
To buy T-shirts, hoodies, coffee mugs, click the link below: