Other sources are:
Teacher Dude's Channel
A citizen journalist using the moniker Teacher Dude's has uploaded numerous photos and posts, including of his own wounds after being beaten by the police for taken photos of a demonstration.
ThirdEye3 on Flickr has photos of protesters holding posters with a photoshopped image of a gun to protest the police shooting, and a photo set tagged #griots.
Sameer Padania from WITNESS' human rights video website The HUB happens to be in Athens for a media conference and has uploaded more than a dozen brief videos of what he saw on the streets.
There are many more photos on the Flickr pages of tom.tziros, has a blog at Trainstorming.
Many more videos on YouTube by searching for #griots