IfyouhavecrazyAdobePhotoshoporIllustratorskillsor you use some otherprogram to manipulateyourphotosextensively, then the DeviantARTcommunitymaybefor you.
Inkling can store thousands of sketches and export layered files directly to Adobe Photoshop and Illustrator (CS3 or newer), as well as Autodesk Sketchbook Pro (2011).