The very next action, before doing any of that, is to back up your palm data. Back it up on your palm, and back it up on your computer.
I believe that using both the GTD add-in and the white paper would be overkill. I think most people use one or the other. And if you go with the add-in, I think it comes with documentation that includes everything that the white paper has. (someone correct me if I'm wrong on that)