Take a normal island from a sea or an ocean. Now, add a giant lodestone(picture Gulliver’s Travels)which forces it into the air. Now place a small city on it with a number of people interested in ancient technology. You’ll then have the Floating Island of Toril. This island floats along in the air supported by the magnetic properties of the lodestone. They use giant baskets on winches kind of like water wells to bring things up or down. The architecture is very unusual(picture a cross between Aztec and Greek), but it serves its function and gives the island a bit of character.
The most important place on the island is The School. It’s a massive series of buildings totally devoted to the study of Antilian culture(look at the Terescence thread in the Setting Forge). They have a number of working prototypes of Antilian machines and artifacts. The guy in charge is a human known as Doctor Samuel Gibson, though his friends call him Doc Sammy.
This is the best(and some would say the only place to go to get information or technology relating to the Antilians. A person who is creative and intelligent may even decide to enroll at The School and learn to create these technological wonders, or an enterprising group of adventurers could be commissioned to find Antilian strongholds and find any books or technologies that might still be there….