Is there anyway to add the new stuff to the top of the file instead of the bottom?

Perhaps the following will be helpful:

use strict;
use warnings;

addStuffToTopOfFile( "New Stuff!\n", 'File.txt' );

sub addStuffToTopOfFile {
    my ( $stuff, $file ) = @_;

    local @ARGV;
    local $^I = '.bak';
    push @ARGV, $file;

    while (<>) {
        print $stuff if $. == 1;
        print;
    }

    unlink "$file.bak";
}
[download]

File contents before running script:

Line 1
Line 2
Line 3
Line 4
[download]

File contents after running script:

New Stuff!
Line 1
Line 2
Line 3
Line 4
[download]

This solution was implicit in Anonymous Monk's reply, but you send a string and file you want prepended to the subroutine. The script makes, and then deletes, a backup file during the process.