mystery failure notice

[Virginia Chism]

I received a failure notice concerning an email I did not send.  I am
attempting to track down how this happened and have hit a wall.  When I do
'tail -f /var/log/maillog' I get current activity.  If I do 'more
/var/log/maillog' it goes all the way back to day one and I don't have time
to slog through FOUR YEARS of maillog when what I need was a couple of days
ago.  Is there any way to select a certain number of items to view in this
log?