Are you looking to import lists from another dashboard? There are two ways, depending on where you're looking to get them from:
1) If you want to grab a list from another dashboard you have access to, make sure you're on All Lists (or All Page Lists), then go to Manage -> Import List. You will see your available dashboards in a dropdown, and it should look something like this:
2) If you're looking for pre-made lists that are not from one of your dashboards, check out the Explore section on the left:
You will find all sorts of lists for you to import into your dashboard.