Does anybody have a map of grover's corners or know how the town was set up?

Answer 1

I didn't find one with a Google search.
I think your best bet is to create one based on the Stage Manager's description of the town.
He provides most of the description in the first few pages of Act One, so you don't have to go too far to gather most of the information.
You might want to check what he says at the beginnings of Acts Two and Three, since he probably specifies where the Webb and Gibbs houses are (in Act Two), and where the cemetery is (in Act Three).
Good luck!