Wow, I've read and read but just cannot find a straight-forward answer to a
pretty simple scenario. :-(

I have two Excel 2003 files (one called ETAP, one called VERT), each has as
its first column Email_Address. Some records in ETAP match those found in
VERT, using Email_Address as the key. There are some records in ETAP that are
not in VERT, and vice versa. Each file can contain several thousand unique
records.

Example ETAP file contents (field names in the first row)
Email_Address MemberCode
Y
N

Example VERT file contents (field names in the first row)
Email_Address State
IL
VA

I'd like the resulting file to include all columns from both files.

Example RESULTING file contents (field names in the first row, in no
particular order, with a dash indicating missing field values).
Email_Address MemberCode State
Y -
N IL
- VA

Your help is very appreciated.