Jiffy, you can find parakeet or bird grit at most WalMart super stores. Regular dirt won't do it, but I read beach sand or sandbox sand works as well. If you have Amazon Prime, they have it there too...
HI in Louisville!!! Hoptown here!!! Just got my first crop of chickies as well (1 week old today) and came to this thread looking for what to treat my FlufferButters (what I call my flock! ) I just put some grit down in their brooder and tossed in about 2Tbs of dried mealworms and seeds...