The two photos below are by GraffitiCreator.org.
You can use the images with attribution to GraffitiCreator.org.
The pictures were taken at the sadly now out of action Platt Fields Park skatepark, in Fallowfield, Manchester UK.
Manchester graffiti for the win.
Nice bit of live graffiti action at a skatepark from SDK.
More skatepark graffiti pics: