As I already pointed out, the "du" tool can help you with this by reporting directory sizes but you will have to calculate percentages yourself.

Here's an example that does pretty much what you describe, go ahead and hammer it into the shape you want:

#!/usr/bin/perl

use strict;
use warnings;

my $dir = join(' ', map { '"'.$_.'"' } @ARGV) || "*"; # Use arguments 
+or default to pwd
my @lines = qx(du -sc $dir);    # Get sizes in bytes, with total
my ($total) = split(/\s/, pop @lines);  # Get total number of bytes
foreach my $line (@lines) {
  if ($line =~ /(\d+)/) {
    printf("%6.2f%%\t%s", $1 * 100 / $total, $line); # Prefix %
  } 
}
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