Here's one way of doing it:
Create a blank layer above the picture and fill it w/ whatever color you want to use. Also, create a color layer below the picture. Go back to the photo layer and select (wanding is the easiest way) the portion of the photo you want. Do not deselect. Select the color layer and hit delete. If you unview the photo layer, you'll notice that the cutout looks somewhat like a stencil (depending on how much was selected).
This can be done w/ multiple layers, just delete each section for each color (so you could have blue hair and a silver face).
The down side to this version is that there is no depth.