it's urgent too....

The following assumes unique surnames. This gets your fixed-width information into an unsorted Perl data structure (hash-of-hashes). sort it as you see fit:

use strict;
use warnings;
use Data::Dumper;

my %clients;
while (<DATA>) {
    next if /^Surname/;
    next if /^-/;
    my ($surname, $firstname, $town) = unpack 'A13A16A20', $_;
    $clients{$surname} = {first => $firstname, town => $town};
}
print Dumper(\%clients);

__DATA__
Surname L20, First Name L20, Town L20 
-------------------------------------------------- 
Chaplin      Charlie         Basel 
Estevez      Emilio Santa    Manica 
Sarte        Jean Paul       Montmarte 
Rikard       Frank           Amsterdam 
Rodin        Paul            Montmarte
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prints:

$VAR1 = {
          'Rodin' => {
                       'first' => 'Paul',
                       'town' => 'Montmarte'
                     },
          'Rikard' => {
                        'first' => 'Frank',
                        'town' => 'Amsterdam'
                      },
          'Chaplin' => {
                         'first' => 'Charlie',
                         'town' => 'Basel'
                       },
          'Sarte' => {
                       'first' => 'Jean Paul',
                       'town' => 'Montmarte'
                     },
          'Estevez' => {
                         'first' => 'Emilio Santa',
                         'town' => 'Manica'
                       }
        };
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