Hi, sorry for the vague information. The address book I finally found was at the top WHITE area of the "Home" tab page in Outlook 2016. This is also called the Quick Access Tool Bar. (I just figured that out.) It is on the far right ,above the funnel icon
for "filter email", and below the "Search People" box. If it's not in your screen you can get it by clicking to the tiny downward arrow in the BLUE area in the upper right of your Home screen and selecting "more commands". Or you can right click the white
empty field at the end, next to the white area Quick Access Tool Bar. Either way will give you a list of things you can add to your "quick access tool bar."
This address book, unlike the one in the New Email page, actually has a menu at the top. Go to "File" and you will see the option to add a "New Entry".
I don't know why Microsoft hasn't simply answered this question in the forum. It is their own website for questions, and yet I could not find it anywhere in response to other people, and never did get a response from them, myself.
Isn't this fun? I hope I was helpful.