I have a couple of suggestions that you might find interesting: Stellas Daemonum: The Orders of the Daemons, The complete book of demonolatry by S. Connolly, The dictionary of demons by M Belanger, The encyclopedia of demons and demonology, Demons of magick, and The goetia of dr Rudd

Also I know a couple of good demonology books but they're the basics so you probably know about them already lol

Have you read No country for old men? It's my favorite book :3