John King can refer to at least four artists:

1) a composer of contemporary classical and avant garde music:
http://www.johnkingmusic.com/site/home.html
http://www.myspace.com/johnkingmusic

2) the lead guitarist for American rock band The Litter
http://en.wikipedia.org/wiki/The_Litter

3) a Canadian guitarist, also known as Papa John King; longtime associate of Long John Baldry
http://en.wikipedia.org/wiki/John_King

4) John Robert King (John) (October 13, 1953 – April 3, 2009) was a ukulele player, classical guitarist and teacher known for his interpretation of classical and Hawaiian music.
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