your problem is clear from different points of view.

• Given you're on XP, you (must) have ActiveSync - it is the way information is exchanged
• It is known fact that no drive mapping, no UNC name or somesuch is done. Why? Because PocketPC does not have good TCP stack (or other network stack). Why it does not good stack? Because PocketPC is weak. Why it is weak? Because hardware is weak.
  -- 'but its not weak', - you say, by device has XXX mbytes of memory and damn fast (my Casio with 150MHz is damn fast, in my opinion; another my device is 400MHz, and I do not comment about current PocketPC-s)
  Nevertheless, someone decided its weak and you do not have proper networking with it. Just that.
• There are several ways to check for files on PocketPC and even execute files there - one of way is to use so-called desktop tools from http://www.rainer-keuchel.de/ Cross-compilation process of Perl use some of this. You may want also to look at perl sources to proper places...
• PerlCE has its homepage at http://perlce.sourceforge.net and wiki at http://perlce.sourceforge.net/cgi-bin/perlce-tcltkce-wiki.pl?PerlCE_And_Tcltkce_Wiki_Page and your question has some relation to this. I think its reasonable to add this and some more related information there.

Also, what functionality do you expect of a module that solves your task? (as you tried to find it on CPAN)

Have fun!