I've been spending a lot more time programming in Ruby lately, but I have OO Perl (and
merlyn's 'perlboot' intro) to thank for having a hope in heck of doing OO anything. In Ruby or Perl, if my classes are specific to the application at hand, I would make that my namespace and then group functions or objects accordingly. Say my application was a tool for writing books, I'd make package names like BookMaster::TOC (for managing tables of contents), BookMaster::Chapter (for managing chapters), and BookMaster::DB (for interfacing with a DB).
Now, if I found that I had some general utility function that was important to me-- suppose I were making a linked list class to make it so I could store each paragraph in a chapter in a list that would be more efficient to insert and delete items from than a vanilla array, then I might look on CPAN and see if there is a fitting namespace, like List::* and then call my class List::Linked.
And just to soothe your naming concerns, there is a whole big section on naming variables and stuff in "Code Complete". So you're not the first person to take it seriously. :)