You won't have a problem once you get into it, this is bread-and-butter stuff for Perl.

Things you'll want to take a look at:
opendir
readdir
stat
time
unlink
system
and as others have pointed out, there's a bunch of modules to help you with this kind of thing too... best of luck with it. HTH!

update: oh, and maybe substr as well, if you don't want to get into regular expressions quite yet...