Found a couple of graff documentary type movies, so I figured I'd post the links.
"Graffiti Verite" aired in 1995 so it's a bit dated, but it is full of sick pieces. The writers give commentary about all aspects of graffiti culture and what it's all about to them, individually. It was worth watching if you like graffiti, and who doesn't?
Here's that [link]
hosted at Hulu.com
"Rock Fresh" had lots of sick art as well. This movie also draws attention to the fact that graff / hip hop / street style clothing is selling like crazy overseas. If you can paint a wall, why not paint a hat and a pair of kicks for our Japanese homies, for fun and mad profit??
This one is also being hosted at Hulu.com at [link]
Sorry if you're not in the continental USA, though, because I'm pretty sure Hulu.com doesn't work unless you're stateside. What can ya do?