/lit/ - Literature

I'm writing a story that takes place in, you know, a generic theme park in Orange County. There isn't a huge focus on characters from the Disney canon, but that being said they do appear in passing as the main character's story unfolds. Is there a good source for what is and isn't in the public domain and how it can be used? I just know this can get tricky, for instance how some characters from the books and fairytales appear or act differently than their Disney counterparts. For instance Monstro is a dogfish named Atilla in the Pinnochio book, not a whale. The story has actually little to do with Disney, but if I can say characters like Hercules and Merlin appear in the background it just gets it a better sense of place.