America's most famous graffiti artist on YouTube
Shepherd Fairey, responsible for the ubiquitous Andre Giant, OBEY, artwork that you find all over America and sometimes in the UK, gives 4 interviews on YouTube.
The medium is the message 1 on Andre
The medium is the message 2 on Banksy
The medium is the message 3
The medium is the message 4 Politics of Aesthetics
To read more about OBEY and Shepherd Fairey have a read of some of his articles.