Dave,
Macro and Closeup can be used interchangeably, closeup is somewhat more generic, while special lenses for this kind of photography are always called macro lenses, and they allow focusing as close as a livesize object on a 35 mm film.
I am not familiar with the Canon lens, but the diopters +1, +2 and +4 can be bought in a set and used to focus closer on a subject. You can buy them in either 52 or 58 mm size to fit either of your lens adapters.
To learn about macro photography I suggest reading John Shaws "Closeups in Nature" if you are thinking about this kind of closeups. It doesn't apply to digital photography in particular, but describes the different options and techniques to get a decent macro photo.