John Elliot has a terrific site, Insights in Jazz, focusing on jazz harmony with LEGO bricks. There's a flashcard file on this site on the Freebies page.
For Blues, Griff Hamlin is my favorite instructor. He's a great teacher and has developed some excellent instructional materials.
Buzz Chewing is a great teacher and terrific jazz-blues guitarist! Located in Columbus, Ohio, Buzz opened my eyes to the necessity of fretboard mastery, thanks Buzz!
Check out Jody Worrell, Guy Fenocchi, Peter Vogl and the fantastic crew at FreeGuitarVideos.com!
If you like jazz guitar, you’ll love Jazz Guitar Online!
Patterns for Jazz was a major inspiration for FretBoard ABCs. Written for all treble clef instruments, you won't find guitar tablature here, but you will find an awesome array of commonly and not-so-commonly used patterns, often with references to the musicians who first introduced them to the lexicon.
Steve Kahn's Khancepts books present a valuable approach that will vastly expand your abilities, particularly in combination with the facility you'll gain from FretBoard ABCs.
Andrew Green is simply one of the best writers of guitar instructional material around. While oriented toward Jazz guitar, Andrew's material will be valuable for all kinds of music.
Soloists wanting to understand what makes solos work over chord progressions will find Connecting Chords with Linear Harmony to be the key that unlocks the mystery.
Randy Vincent opens the door to chordal mastery with a masterful presentation of drop 2, block chords and adding three-note voicings to the repertoire.
Shawn Persinger has a great new book on guitar books, The 50 Greatest Guitar Books.
Lastly, Herb Ellis’ book All the Shapes you Are is a fine addition to every guitarist’s library. He offers a number of essential riffs built on chord scales that will enhance solos and chord solos in any style.
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