Simpliy put all titles in a hash as key then print out all keys.
This will elminate all duplicates.

use File::Find;

my %titles;

sub wanted
{
 if( $_ =~ /\.html?$/)
 {
   my $name = $File::Find::name;
   open ( F, $name ) or die "$!: $name\n";
   while($line = <F>)
   {
      if($line =~ /<title>(.+)<\/title>/i)
      {
         $titles{$1} = " ";
      }
   }
close F;
 }
 foreach my $key (keys %titles) { print "Title = $key\n"; }
}


find( \&wanted, "/unixpath/webfiles" );
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