Macs (assuming you are talking about Mac OS X) come ready to run Perl without any standing-on-your-head involved. I have a folder called "Projects" (you can also use your "Sites" folder, esp if your work is web related) and I put my Perl programs in appropriate subfolders therein.

Write you scripts using any editor that will utilize Unix line endings (most all will... skEdit or TextWrangler or Smultron), save them, go to the terminal and chmod +x yourscript.pl, and then perl yourscript.pl

update: added links to text editors