http://en.wikipedia.org/wiki/Music_lesson

http://en.wikipedia.org/wiki/Lessons

http://www.ultimate-guitar.com/lessons/

http://www.guitarists.net/lessons/

http://www.mcli.dist.maricopa.edu/tut/lessons.html

http://www.gibson.com/en-us/Lifestyle/Lessons/

http://www.musikalessons.com/

http://gelessons.com/lessons/

http://www.mathgoodies.com/lessons/

http://www.thefreedictionary.com/lessons

http://www.worldwidelearn.com/online-courses/music-courses.htm