Chris,
First, hit the bait shop. Get your squid and spearing (Silversides) there. Be sure to ask where the Spearing come from, as you want Canadian Spearing. Anything caught or collected here will be packed in formaldehyde. Then, stop at a supermarket for shrimp, scallops clams, what ever you can get. If you really want to, go to a fish market, and buy small pieces of pretty much what ever they have that you haven't gotten cheaper already. Go to an Asian store and get your Nori, then stop at Fishy and get some Cyclop Eeze. Grind it all up, and pour it into those little ice cube trays, and freeze.
I have learned that Octopus gets ignored in my tank, and squid is a big seller. Everything else falls somewhere in the middle.