The last link under the Largo Fundamentals is The Premium Level. Click on Premium Level and scroll down In bluish letters you find this note:

Free trial users can use their CC (Coupon Code Number) and get the Premium Level 50% OFF for the first month. That’s only $20 for a whole month PLUS you get MTM eBook 1 (PRINTABLE) and lifetime access to the interactive eBook (INSANE VALUE). CLICK HERE TO UPGRADE.

If you have purchased the Premium Level, then you will find the MTM eBook button. n on the page where you access the course. Scroll below the Forum Topics until you get to MTMebook. Click the Access button. https://mysterytomastery.com/members/

Currently, I have the Foundation Level Membership. I think you should find the PDF version available when you purchase the Premium Level.

The Premium Level includes Allegro and Presto Status Stages as well as Foundation level Status Stages (Moderato, Andante, Adagio, and Largo); plus downloadable MTM Book 1 PDF; plus access to the worldwide MTM community via our WindWorks Forum.

$39.99 / month

I have a paperback copy I bought from the WindWorks store. I bought it with a WindPack.
https://mysterytomastery.com/product/mystery-to-mastery-book-1-hard-copy-windpack/