These are just some brush sites that I've gone to and possibly downloaded from. This will probably be updated as I go along. XD

Miss M::photoshop brushes & graphic resources
Spy-Glass.net
Timo2000
Brush Fed
Short-Things
Greeneye.net
2D Valley
Absolutetrouble
OgeeFire
Aethereality.net
Annika Von Holdt
Kakii.com
Echoica.net
Beautiful-Sin
Chinaberry
Classic.tere-art
Celestial-star.net
Brushes at Deviantart.com
Darkmercy-brushes
Dubtastic Design Labs
Elizabeth the Painter- Brushes
Fractured-Sanity.org
Hybrid-Genesis
Imprints
Obsidian Dawn
List of Brushes
Misguided Buddha
Square Pretties
Studio911Design
Studio Brushes
Unknown Brushes
Magitek-Designs
V Brush