Actionscript drag 'n drop

Hi im wanting to create a drag and drop sort of jigsaw puzzle.

Basically their is a outline of an image, about 10 pieces on the side, and i want to be able to drag them into the ouline and they snap into position.

Could anyone assist with some example of code, perhaps bit sof .fla docs etc for me to play around with and get an idea how to build this type of app.

THANKS