Are they just out of chick feed? Or any kind of poultry feed? What did your local feed store recommend? When are they getting more? Honestly I'd just feed them whatever I could get my hands on as long as it's for poultry. Preferably some type of grower or something. Or grab some COB, grind it down yourself, and add some protein into it (there are calculations for this).
I keep a mixed flock so it's basically a free for all between the chicks, adult hens, turkeys and now ducklings. I just put out both types of feed and let them eat what they want. The neediest birds do take priority. For example the turkey and ducks have specialized needs but the chicks and hens can eat the turkey/duck food without ill effect.
Chin up, you'll find something! Just start making some calls tomorrow.