I just stumbled onto a University of Texas site, Dante's World.
It is very cool. You can enter either the Inferno, Purgatorio, or Paradiso. Every few cantos have options to view famous artistic renderings of those scenes, such as those by Blake. It also gives key images, explains some lines, gives an audio line or two in Italian, and offers study questions.
All in all, a worthwhile site, even for the artistic renderings alone!