The use and require functions will search directories in your @INC array to find a requested file. Perl is just telling you it couldn't find the particular file. I can think of at least three possible problems, and ways to solve them:

1. The module is really not installed on the box. Find and install it.
2. The module is installed, but the directory is not in @INC. Two possible remedies: either add a

   use lib '/where/it/is';
   [download]

   to your code to give Perl an additional directory to search, or set the PERL5LIB environment variable the same way.
3. The file is installed, and the directory is in @INC, but there's a permission problem (you can't read the file or search the directory). It's more likely this would've produced a permission error than a "Can't locate", but it is possible. Carefully check permissions on all directories and the library file: make sure files are readable ("r" bit in permissions) and directories are searchable and readable ("x" and "r" bits).

HTH