In the Star Wars Prequel trilogy, we are shown only one side of Tatooine, while the other is on the far side:
What does the other side (hemisphere) look like? Is there a map of the area?
We see a ship approaching Tatooine from a different angle in Star Wars: The Clone Wars. As you can see, the topography is very similar to that of the other side.
This image below comes courtesy of Star Wars: The Old Republic (and as such is non-canon) but again, we can see the general character is that of a featureless desert-world.