AskAManager discussion

I'm an office manager and the main front desk/telephone contact for our office. I'm looking for books to improve my skills, particularly when dealing with people who are upset because other people gave them wrong information (or they think they did), policies changed, etc. Our office just went through a "Verbal Judo" training, which was very helpful but focused on generating compliance (i.e., getting people to do things), which is a small part of my job. I spend more of my time 1) answering questions / sharing information and 2) calming people who don't like the answers they get, without allowing them to escalate up to my supervisor without good reason. I'd love to learn more about best practices for this kind of work. What books can you suggest? Thanks!