"Will your Fretboard Theory book help me transcribe songs?"
My guitar theory book and DVDs may not focus on the skill of transcribing specifically, but do teach guitar players how to understand keys, scales, chord progressions and other important musical elements that transcribers use to figure out songs by ear. So if your goal is to better understand the music you play and better anticipate what's happening in the songs you're listening to, then yes Fretboard Theory will help.
