Some Youtube videos are preceded by short advertisements. You can find the music elsewhere if you are willing to search.
Song for Nino by Virgin Forest.
http://www.youtube.com/watch?v=mbIOYdFcqhY%2noredirect=1
Hard Times Come Again No More by Stephen Foster. Performed by Iron and Wine.
http://www.youtube.com/watch?v=95itEHED8Hk
Lute Concerto in D major RV 93 (transcribed for guitar) by Antonio Vivaldi. Matthew Marshall, guitar, and the New Zealand School of Music String Orchestra conducted by Donald Maurice.
Kindergarten Wall by John McCutcheon.
http://www.youtube.com/watch?v=j9HfZNuPOQ4
When My Boy Walks down the Street by Stephin Merritt. Performed by the Magnetic Fields.
http://www.youtube.com/watch?v=aaUnv4dPrvU
Girls Just Want To Have Fun by Cyndi Lauper, from the Memphis Blues Tour (you'll have to change the lyrics as you listen).
http://www.youtube.com/watch?v=NrSYt7LIj2Q
Gnossienne Number 4 by Erik Satie (transcribed for guitar). Performed by Enrico Altavilla.
http://www.youtube.com/watch?v=PNOLPTJMh10
So You Want To Be a Rock n Roll Star by The Byrds. Performed by the McGuinn Band.
http://www.youtube.com/watch?v=BdoXeAUNz0w
This version, a cover by someone, shows a Rickenbacker 370/12RM (Roger McGuinn model).
http://www.youtube.com/watch?v=9O5DuVOssmk
He Was a Friend of Mine (traditional, with new words and arrangement by J McGuinn).
http://www.youtube.com/watch?v=Nb8WH3ewNIE
String Quartet No. 15 in D minor K.421/K417b by W. A. Mozart.
Modern Boys by Brett Anderson and Bernard Butler. Performed by Suede.
http://www.youtube.com/watch?v=PCQOoGXbIHU
Casta Diva from Norma by Vincenzo Bellini (you decide who was better; my preference is Caballé).
Maria Callas
http://www.youtube.com/watch?v=TYl8GRJGnBY
Montserrat Caballé