The guild I belonged to when I lived in Ontario had a very large library. I was one of the librarians, there were 3 of us. We had an annual budget. All the books were quilt related, but we tried to cover all topics, new trends, etc. We would ask members for book suggestions as well. The books were stored at the head librarian’s house, we had to lug the books to the meetings every 2 weeks - a big task and we rotated what we would bring as there was just too much setup involved to bring the entire library. Once a year we would sell off books that were dormant.
I agree that having specialty rulers/templates would be a great addition to any guild library!