No, it's not in the FAQ although I should probably make an entry on the subject.

Just look at the properties box of any playlist and you might be able to figure out how to do it. Remember that "always randomize contents" actually means "always randomize only the immediate children of this playlist". So, if you had a bunch of artist playlists under a "shuffled artists" playlist, and each of those had "always randomize contents", then you would get blocks of random artists, with the songs internal to those blocks randomized.