Can I import video from my Sony mini DV handcam tapes through the 4 pin DV port to my MacBook with a usb-c port? Where can I find this cable? Thanks

I haven't done this myself, but I think you can connect your camcorder to your Mac with whatever cable came with the camcorder. A firewire cable is what is normally used, but if your computer doesn't have a firewire port, you can connect through the thunderbolt port using a firewire to thunderbolt adapter.

Here's a link to the online Apple help menu that explains how to import from tape based cameras:

http://help.apple.com/imovie/mac/10.1/#/mov6af9c94c1

-- Rich