Texture color with vertex paints I have a black and white textured 3d model. Is there any way I can vertex paint the model and have the vertex paint serve as a way to "colorize" or change the color of the black and white images to what the vertex colors are? 

Example: in gimp, you have a black and white image. You go to the top and pick colors > colorize > select a color. It changes the hue of the white while still keeping dark things dark.
With Blender Render engine selected and a regular old non-node-based material, go to the material properties and check Vertex Color Paint. This will make the diffuse color of the mesh equal to the diffuse color of the material times the diffuse intensity of the material times the diffuse texture of the material times the vertex color.

After you're done you can bake the vertex colors to a texture if you want and use the compositor to combine them for use in a game engine if that's your thing. Or, use a shader and engine that can use the vertex color if the texture is tilable.