I've been making my food for a while now. The biggest costs for me are the frozen food you buy from the LFS. Those are the real killer. Shrimp, clams, squid, and everything else you get from Wegmans is really cheap.
Buy the smallest (which is the cheapest) shrimp you can find. Oddly, the larger clams tend to be cheaper than littlenecks, and you get more meat. I'll share pictures and my exact recipe the next time I do this. If you are being frugal, you can always pick things up on sale and freeze them until you have everything to make a batch. I'm thinking about hatching my own brine shrimp next time too.