I found this
guide on making a business phone call on the Internet and think it is a reasonably good reference for office hours calls. Not that any of you folks need it, but I am providing it just in case.
1. Remember that a business telephone call is comprised of three components: the beginning introduction, the middle bulk of the call, and the end summing up.
2. Say everything that you need to in order to explain your reason for calling. State when you will return the call or request that the other person call you back. If you have to leave a message, be concise.