I got it working by reordering my code and initializing properly (and by digging through a Perl textbook...).
Thank you all for your advice!
Now I have a Net::OAI::Harvester specific question - so far I've been able to retrieve titles and identifiers for all records but is there a way to default to the entirety of a record? I essentially want to be able to see all metadata associated with a given record in a given repository. I'm not sure if this is beyond the scope of this particular harvester (which has so far been awesome) but if so, how would I go about adding that functionality? By adding a distinct module? If so, any advice as to which?
Again, thanks for all the help.