Now with Google's MapMaker, you can edit Google Maps, build your own maps. Fun, fun, fun!
I've spent a few minutes playing around, adding a few places I know that are not on the map, and its pretty easy to use. Its kind of a open approach to building the map since changes any user makes will be moderated by other users so as to improve accuracy.
I'm still not sure ( I haven't checked) whether locations have been geotagged for direction finding, but if not, I guess it will be happening at some point, so the more the locations and sites on the map the better.
Check out the Official Google Africa blog for more details.