Amazon occasionally shows shipping delays. Even so, it actually ships the books very quickly, within days.
also on kindle
Intervals Wheel (PDF)
Preview book (PDF)
Answer sheet (PDF)
Preview book (PDF)
Intervallic Fretboard

Guitar Fingers: Essential Technique in Pictures.
Intervallic Fretboard: Towards Improvising on the Guitar.
The CheatSheet Music series.
MUSIC PAPER series. A series of blank manuscript paper in NOTEBOOK and POCKETBOOK formats for all instruments.
Guitar chord diagrams; Tablature / standard staff (combined); Standard notation; Guitar TAB; Standard staff + TAB; Chord + ...staff/TAB (chord combos); Ukulele chord diagrams.