There isn't much written material on the subject. Andrew Martin's "Starting Out: The Sicilian Dragon" has a couple games and Martin's thoughts on the opening. Your best bet is to search a database, take a bunch of games from well known players, and start looking them over yourself. Also, now that I think about it, one of the NIC Yearbook's has an article on the Dragondorf by Simon Williams, who is responsible for bringing it back into fashion(slightly). Check it out. 😀