Thank you for your replies.

So far the best example of exception handling I have been able to find is from the bioperl project.

It would be very insightful if someone could create a skeleton of classes using Error.pm that illustrates its use in exception handling. Another item of interest is the way that Error.pm implements the syntactic sugar for the  try {} catch {} except {} otherwise {} finally {}; statement.

Also of interest:
The Problem with Perl's Exceptions.
Exceptions,ExceptionsClass, and a quick hack.