[Question] Game sheet music

Hi everyone =)
I am new here
And I have a question about sheets of Final Fantasy ix:
I want to buy a book of the sheets from the game, but the book named ‘Final Fantasy IX Piano Collections’ includes the "harder" versions of the music, and I want an easier version of the sheets, like the ones in this website: http://ffmusic.ffshrine.org/ff9sheet/ff9-sheet-music.php
Do you know what is the name of the book in the website? download 1 of the sheets and see the scannings, I whould like to have this book with easier versions so I wanna know the name of it…
Thank you!
Mor.O:]