Hey UncertaintyLich! Welcome to the community!Yes, you can use Sphere on a Mac. The easiest option I guess is to download the windows version and use it along with Wine. Another option is to get one of the several Mac builds of it. If the wiki were up I'd happily point you the way. It depends on what Mac you are running. I'm sure N E O will point you a good link to use.
As with anything programming it'll take time and willingness to do it, it's not quite so easy as writing a novel, but it can be very rewarding.