I write a free monthly teaching newsletter that visually examines theoretical concepts for guitar. Anyone can sign up to receive it and the sole focus is to help guitarists make connections to become better guitar players.
If you are trying to expand your knowledge base and understand the guitar, you will find valuable answers here. Everyone who subscribes immediately gets all the back issues too (over 50 pages). This newsletter focuses only on teaching and it is FREE.
You can check out the October 2000 edition without signing up at the page listed below. The next edition will be published on the 15th of the month.
Thanks, I hope this helps.