- eBookThe Advancing Guitarist's WorkbookMichael Gumley
- eBookLittle Ninjas Guitar Method BookMichael Gumley
- eBookThe Guitar Ninjas Orange Belt BookMichael Gumley
- eBookThe Ultimate Adult Beginner Guitar Method Book For The Hobby PlayerMichael Gumley
- eBookThe Guitar Ninjas Green Belt BookMichael Gumley
- eBookThe Guitar Ninjas Yellow Belt BookMichael Gumley
- eBookThe Guitar Ninjas Blue Belt BookMichael Gumley