Haven't had a shipment in a long time, but cans are all over the place, but definitely easier to find at a bar than a store. No kegs. Union Square Whole Foods is a good place to start.
It's usually all over the place, but I don't think anywhere has received shipment of 2016 gose yet, so anything you find is likely left over from last year.
Usually it seems to hit in big deliveries and can be found at most good shops, but then tends to sell quickly. Whole Foods is usually where I find it.