You're better off using File::Copy :

#!/usr/bin/perl

use strict;
use warnings;

use File::Copy qw/move/;
use File::Find;

use constant TARGET => 'D:\\jude-test';

find sub {
 move $File::Find::name, TARGET if -f && /\.(contrib|keep)$/
}, @ARGV;
[download]

(Yes, this shebang is kinda ankward for a Windows script :)