I mostly skim my gigantic, embarrassing personal comic collection when I'm feeling off or if I need a quick reference. I have about 250 issues I consider "important" with Zatanna in them on my HD for quick access and a cnc folder of saved pages and important images (Gaster, her house, in-game fanart). I have several private entries with in-game notes, important ooc notes, and whatnot. I get bored doing relationship charts pretty quickly, so I never keep them up to date.

I have some wikipedia articles and website links, but they're mostly on locations or historical events, etc. Weird little bits of things that I'd rather not just pull out of the blue. I already own books on sleight of hand, stage illusions, the history of magic, and her various ancestors, but I have found myself reading more about that sort of thing for the sake of playing her.