I have a pretty decent experience with tile based 2d games and I would like to try to create a mixed 3d-2d game. To 3d elements will be very simple (ground, walls and water), all other elements will be 2d sprites drawn onto this 3d map. (I am envisioning something similar to Final Fantasy III for iPad, top down view, always the same angle)
Now, here is my question: What are the technical aspects of implementing a 3d tile engine? Are there some good examples on how to do this? Basically I would like to create the maps the same way that I would do in a 2d tile based game.