I sent two orders to the Store back-to-back and then tried to email shipping@lettersandlight.org (with order numbers) so they could combine my orders into one package.

The email bounced back. (Maybe I didn't use the right address.)

The error message:

----- The following addresses had permanent fatal errors -----

(reason: 550 : Recipient address rejected: User unknown in local recipient table)

I don't believe that's the correct address.

Try using the store contact form.