How crucial is cornmeal?
The cornmeal gives some texture to the end result, and helps prevent the bread from sticking to the surface by acting as little ball bearings. It's not essential unless you have a very sticky dough, then I'd suggest using baking parchment if you have it. Otherwise, if the dough is not super sticky grease the pans really well and you ought to be fine. 

A good substitute for cornmeal is semolina, but if you can find that cornmeal isn't likely to be an issue to source.