Say I had a map like the one displayed above. What would be the best method of creating a collision map for each individual state where I can click individually?
Convert your image to grey-scale. Make sure you have no two states that have the same grey. (You have to tweak the image.)
Have an infrastructure that maps the grey colour to a state.
Then when you mouse-over the map, pick the pixel colour that is under the mouse pointer, and search for it in the map.
You'll know what state you want to select this way.