Sorry, the Users Guide isn't here... (pretty lame, huh?)
You might find it on-line, although probably in an unfinished form, from the Mail Drop Information Web Page <http://ackmo.baylor.edu/files/Mail_Drop/info.html>. If it's finished, then it should also be available via anonymous ftp from <ftp://ackmo.baylor.edu/pub/bell/Mail_Drop/>. Stay tuned...