I'd suggest researching into Disney's Atlantis flick, behind the scenes. Their artists sketched everything from Mayan ruins to asian temples to
adapt the look and feel of their Atlantis.
There's also a book completely about the Art of Star Wars, that would be a good source too, you can likely get it at the local library...
Of course, given my bias for Atlantis being South America, I'd suggest using such ruins as a key part. Ziggaraut step pyramids, red, white and black
stone (as mentioned by Plato), etc.
[edit on 24-9-2004 by Gazrok]