The official FAQ is maintained on the main Istaria page. You can find it here.
If you have further questions, there are a few places that can provide more information.
You can ask a question on the player forums:
The knowledge base has lots of technical questions and answers:
Browsing around the community site:
But the best place to find information and learn about the expansive world that is Istaria, is to simply download the game, create a character and interact with all the other players. There are many who like to play the Tour Guide of Istaria mini-game. So ask around if you need assistance as you explore the towns, create items and buildings, and fight to destroy the Withered Aegis!
If you don't have a copy of Istaria, a free download is available here: http://community.istaria.com/pg.php/download
If the links above don't cover your questions, please contact customer support at http://support.istaria.com