Certainly File::Find can help you out.

#!/usr/bin/perl -w 
use strict;

use File::Find;

my @qualifiers = ();
my $today = time;
my $ten_days = ( 60      # seconds in a minute
               * 60    # minutes in an hour
               * 24    # hours in a day 
               * 10 ); # the number of days


sub process_file {
  push @qualifiers, $File::Find::name if is_ten_days_old();
}

sub is_ten_days_old {
  # File::Find has done the following for you:
  #  - chdir to the directory where this file resides
  #  - set $_ to the basename of the file
  #  - set $File::Find::name to the fully-qualified name of the file

  # Don't check ages on directories.
  return 0 if -d;

  # stats $_; ninth item is modification date
  my $age = (stat(_))[9];

  # returns true if old enough, false if not
  return $today - $age > $ten_days;
}

find(\&process_file, @ARGV);

# Print all the files qualifying:
foreach (@qualifiers) {
  print $_,"\n";
}
[download]

Then invoke it like this:

C:> perld tendays.pl C:\this\directory\please
[download]

(I think the invocation is right; I 'm a Mac and Unix guy, not Windows. I've run this code on OS X and it works OK there, modulo the file specification syntax being different.) The key is the is_ten_days_old() sub, which tells process_file() which files to keep.

I highly recommend the Perl Cookbook; if you don't have a copy, you should consider getting one. This is a modification of Recipe 9.7, Processing All Files in a Directory Recursively.

You could do it yourself, but File::Find is faster for you to get the job done.