DBD::Pg is a Perl DBI driver for the PostgreSQL database. While both Perl and Postgres are excellent products, getting them to work together is somewhat challenging, since the driver needs to be linked with the Postgres libraries (which are not always going to be installed on the machine you're trying to access the database from). This is further compounded by the fact that the Win32 distribution of Perl does not provide a pre-compiled package for this driver. So, after trying (in vain) to find a pre-compiled driver that would work with the versions of Perl and Postgres that I was using, I made the package that's linked below.
This package was compiled using the Cygwin distribution of Postgres and ActiveState's ActivePerl 8.3.0 (build 805) for Win32. It should work for that build of ActivePerl on Win32, and at least version 7.2 of Postgres as your database. If you can get it to work in other environments, more power to you. However, this binary is being provided without support; if it doesn't work, you'll have to figure out what's wrong, or compile it yourself.
Download the driver as a zip file containing a ppm package.