One of the quirks about being a guitarist is that our Diatonic music system is built on thirds and our intrument is built on fourths. That fact along with the fact that most of us are uncomfortable reaching for more than 5 frets with our left hand obfuscates the parameters of music theory on the guitar. Nevertheless, every musician MUST know music theory in order to develop into a complete musician. I can help you with this. Go to http://www.fretboardtheory.net You'll find an upcoming workshop and some downloadable lessons. Take your time . You will expand your horizons on your fretboard and your vision for what's possible.
If you are an intermediate to advanced player and you feel like you're "stuck" in what your guitar is yielding for you, don't feel alone! everyone 'plateus". At some point you have to address how music theory lays out on your fretboard. I have my own method of revealing this to my students. which I call "FRETBOARD THEORY" http://www.fretboardtheory.net which I teach here in Austin. A sample video lesson is in the 'video' section here. Skype lessons are available. Let's talk guitar. Leon