Huh. Everyone wants to type a lot. :)

You're trying to create a "Hash of Arrays". Check out perldsc, the "Perl Data Structure Cookbook" for lots of examples. Here's how I created it from your example data:

#!/usr/bin/perl
use strict;
use warnings;

my %hash = ();
my $key;

while( <DATA> )
    {
    chomp;
    
    if(    /^(\S.*)/    ) { $key = $1 }
    elsif( /^\s+(\S.*)/ ) { push @{ $hash{$key} }, $1 }
    elsif( /^\s*$/      ) { next; }
    }

use Data::Dumper;
print Dumper( \%hash );

__DATA__
Honda
 Civic
 Accord

Toyota
 Camry
 Corolla
 Tundra

Nissan
 Maxima
[download]