my %ids = ();
my $curpos = 0; # position within the file
while ( defined( my $line = <HANDLE> ) ) {
    # we want 
    my ( $part_left, 
        $part_right ) = split( /\s*,\s*/, $line );

    my ( $id, $name ) = split( /:/, $part_left );

    $ids{$id}->{$name} = $curpos;

    $curpos += length( $line );
}

# later when we want to look up a record
sub get_record( $ $ ) {
    my ( $id, $name ) = @_; # arguments
    my $filepos = $ids{$id}->{$name};
    seek( HANDLE, $filepos, 0 );
    my $line = <HANDLE>;

    my ( $part_left, 
        $part_right ) = split( /\s*,\s*/, $line );

    return( $part_right );
}

# e.g.
get_record( "daamaya", "Daniel R. Amaya" );

# process $line