Getting a grease pencil stroke

Does anyone know how to get the data from a grease pencil stroke, such that it could be converted into a set of points?

There’s an option in Blender 2.55 for converting the Grease Pencil into a Path or Bezier Curve. It’s in the Properties panel, when a new Grease Pencil layer is built.

I mean how can I do this with python, for instance, say I want to write a script that prompts the user to make a grease pencil stroke, then when the stroke is made, it gets a set of the 2d coordinates that the stroke is at on the screen, how could I do something like that?

Well, since what you want is already more or less implemented, why don’t you start by checking the open-source code developed by BF for the Grease Pencil panel? It’s certainly all there you just need to change it to fit your needs.