While I was Associate Editor at Guitar One magazine, I published numerous articles and columns on playing the guitar. Any issue of Guitar One published between the summer of 2000 and the final issue in the summer of 2007 will have a significant amount of my writing in it. Contributions included performance notes on how to play the transcriptions of songs found in every issue, "Strum It" arrangements of songs especially suited to acoustic guitar and voice, the "Acoustic Cafe" column which addressed the techniques common to acoustic guitar in greater depth, and occasional full-length articles. Unfortunately, all this writing has no web presence at the moment. I am looking forward to uploading all this text in the near future. Stay tuned.
Here are some other links and lists that might help your guitar playing.
The Beatles remain a high standard for guitar music. If you'd like every recording they released to the public as a band, you can find it on these albums:
Please Please Me (March 1963)
With the Beatles (November 1963)
A Hard Day's Night (June 1964)
Beatles For Sale (December 1964)
Help! (August 1965)
Rubber Soul (December 1965)
Revolver (August 1966)
Sgt. Pepper's Lonely Hearts Club Band (June 1966)
Magical Mystery Tour (November 1967)
The Beatles (a.k.a. the White Album) (November 1968)
Yellow Submarine (January 1969)
Abbey Road (September 1969)
Let It Be (May 1970)
Past Masters, Vol. One (singles from 1963-65)
Past Masters Vol. Two (singles from 1965-70)
I would also highly recommend the Beatles "Anthology" series of albums for brilliant versions of their songs as they were working them into their final forms. Many of these "in-progress" mixes show off the songs with just acoustic guitar and voice, and also show how amazingly flexible they were as musicians and songwriters. For example, George Harrison recorded a demo of "While My Guitar Gently Weeps" in D minor, capoed up five frets to G minor. Then, a month later, the full band recorded it in A minor, played in open position on guitar - a completely different set of chord shapes!