For Goetic entities, I really like Goetia Pathworking by Corwin Hargrove. The more I use it the more I like it and it’s become my go to for those entities.
For non Goetia I also call on the entities in the Book of Azazel by E.A. Koetting and maintain my relationships with them. There are one or two from Kingdom’s of Flame I still keep in touch with and I will get back to meeting more of them sometime.
We have a book recommendations thread, but it’s general (not just goetia) for one thing and also not all recommendations are in that as it’s a bit of a self serve “add it if you like it” thread. I’m sure there are lots of great topics that I just don’t know about to add myself.
One of the entries there for Goetia:
So the search here is richly featured and lets you search by title, post content, category, who posted and date etc, I’d start with a basic “book goetia recommendation” search string on the whole forum and narrow it down from there.