Do you have your email address specified in the globals file for either of these two values:
$WAGLOBAL_Contact_Email_CC = "" ;
$WAGLOBAL_Contact_Email_BCC = "" ;
The email should send to the customer as well as the email address listed in these settings. If you do have the email address specified here have you tried more than one to see if the address is the problem? A good test might be to go through the store and make a purchase with this email address to check that you are able to get the receipts.