Where to get Perl
Do you have Perl?
Try typing "perl -v" at the command line. You should get a version statement.
$ perl -v
This is perl, v5.8.6 built for darwin-thread-multi-2level
(with 3 registered patches, see perl -V for more detail)
....
Perl source
You will need a compiler, a shell, and some system libraries. Perl's Configure script will tell you if you're missing something.
If you're on Windows, you may not have a compiler to use. Look onward to Vanilla, Strawberry and ActiveState.
Windows Perl: Vanilla/Strawberry
Vanilla and Strawberry Perl are two Windows Perl distributions that come with a compiler and enough of an environment to get Perl compiling and running on that platform.
Unless you have a very specific need, you want the Strawberry Perl distribution.
Windows Perl: ActiveState
Originators of Perl on Windows, and still very much involved in the community, ActiveState releases their own version of Perl with a module installation system called PPM. If you don't want to deal with the "hassle" of managing your Perl install yourself, this may be for you.