The iTunes Store is now listing the ¡UNO! ¡DOS! ¡TRÉ! songbooks available for download at $16.99 each.
Published by Hal Leonard, who have printed most of Green Day's catalog, these songbooks provide note-for-note guitar transcriptions with tabs for each song in the trilogy.
These ¡UNO! ¡DOS! ¡TRÉ! songbooks are the digital versions of the physical books released last year and that are available on Amazon (¡UNO!, ¡DOS!, ¡TRÉ!).
If you're an owner of an Apple iDevice running at least iOS 7 or a Mac running OS X Mavericks (10.9+), you can get a sample of each book by accessing the iBooks Store on your device or computer. The sample will download and you can get a taste of what each book is like.