Man, I've been trying something similar to that for a while now, in my Columbus, Ohio thread, which I started largely to find buddies who might be willing to go in on cases of things like Grande mozzarella. And although probably 7 or 8 central Ohioans have contributed to that thread, and at least one person has even shown considerable interest in splitting a case of Grande cheese, nothing real has happened yet, excluding the case of pepperoni that Nick (weemis) and I are going to split in a few days. But the pepperoni deal probably would have happened even if I had never started the thread, since Nick and I have actually met up a couple times already, and because we are both very active participants on these boards.
It's frustrating, especially because I'm willing to buy 15 or 20 lbs of cheese, which should make it easier to find people willing to split the rest. But I guess there just aren't many people who, like me, make pizza every day for months straight. Since I make so much pizza, I guess I have kinda lost touch with the reality that 5 or 6 lbs of cheese is a buttload to most other people; even most other pizza geeks.
It's also frustrating because of the possibility that people might make a commitment to buying part of a case and then back out after you buy the stuff. And I really don't want to deal with the various hassles involved with shipping to other members or having them ship something to me. So trying to coordinate such an effort has not been fun. And I still don't have any Grande mozzarella.
But you know what? More central Ohioans will eventually become pizzamaking.com members and see my Columbus thread, which means eventually there will be more local folks who will consider doing group buys. I've planted the seed, and it's sprouting a little. So I encourage y'all to consider doing the same thing in an effort to create a network of members in your area. Maybe you'll get more bites than I have.