Your current data can have some problems. Maybe they are "flat" (just a list of people), they are incomplete, they are inconsistent (company name's not written in the same way), they are duplicated. And they can have many other limits, but they are your starting point.
So, go on: you can import them in your new "living address book" as your starting point. You can import your entire address book from your smartphone, or you can import from Outlook, Thunderbird, GMail, LinkedIn, or from any vCard or csv file. In essence, you can import from every software you are using today.