Help finding users on system

I am trying to find where virtual-min stores the user information. More specifically I need a flat file of all the email addresses on the system. I have checked /etc/mail/virtuser table, but I do not see some addresses that should be there.

For instance:

cat /etc/mail/virtusertable | grep example example ssmith test.empiredd

but if I go virtualmin -> -> edit mail and ftp users -> I see several that are not listed in the virtusertable file.