Use a catalog or in Word XP and later it is called directory type mailmerge
main document that uses that data source and insert the fields that you want
in the order that you want them into the cells of a single row table in the
main document.  Execute the merge to a new document and then insert a row at
the top of the table in that document and type field names into the cells of
that row.  Save that document and use it as your data source.