Library organization

Hello there everyone, I've been hired in a small Library to fix the organization of books. My question is does anyone know of any helpful programs or methods that can help me to catalog the books in the library and then two subcategories them I've always loved books but I've never worked with them. Thank you to all who help.

The Librarians Who LibraryThing group might be able to help:
https://www.librarything.com/groups/librarianswholibrar