Run a cable from either the switch or the lights to your new location and install a receptacle. It depends on how it is wired, which location you can run the power from.

Hmmm...20A breaker for 2 ceiling lights? Have you checked the size of the wire to that breaker? Is it indeed 12/2? What else is on that circuit? Rare to see that size of breaker on a simple light circuit.

It is 12/2 wire and a 20amp breaker, there is power going to 2 lights then a switch and that's it, probably done in the 70's

It's in the kitchen of a 40's house and I'd like to add a receptacle for the fridge

We have two walls and the ceiling down to the studs and I'd like to do something while it's open

I guess you're somewhat lucky to have #12 wire there! Are you 100% POSITIVE there's nothing else on that circuit, though? It's mighty strange to have only two light fixtures on a 20A circuit.

If everything is just as you've said, #12 wire to only two lights on a 20a breaker, then... well, that's an easy as pie extension to make a receptacle. Just make sure you connect everything appropriately and don't put the fridge on the switch by accident.. that'd be awkward to explain later ;)

Are refrigerators required to have a dedicated circuit in some locales?