Acoustic Guitar is the magazine for all acoustic guitar players, from beginners to performing professionals.
Acoustic Guitarists' Annotated Guide to the Internet
A site devoted to all things of/or relating to acoustic guitar. Includes both reference information and links to other sites.
Chords Note Player
This is a cool product if you own a Mac computer. It is an inexpensive App that can be purchased from the Apple store that lets you enter a chord chart for a tune and then play it as a backing track for your practice. You can transpose the tune to any key and adjust the tempo to your personal preference. The sound quality is very good.
Guitar Home Page
Dan Smith is the author of this site that has some of the best guitar scales and chord theory information you will find.
Notes by Jason Nieh
If you can't find a guitar-related link here, it probably doesn't exist.
This site is dedicated to the acoustic guitar, its legend and lore. It features a discussion forum which is one of the best sources of acoustic guitar information on the web.
Online Guitar Community
An on-line community and education-based site for guitarists. It's designed to enable guitarists of all skill levels and styles to share information about all things guitar over the Internet.
This site features a fantastic graphical display of chord shapes, including 6ths, 9ths and other jazz chords. All chords are available as MIDI-files so you can hear as well as see them.