my @array=(
     ["def","456","$%^"],
     ["abc","123","!@#"],
     ["ghi","789","&*("]
        );

#code to sort the aoa here
@array = sort { $a->[0] cmp $b->[0] } @array;

for my $i ( 0 .. $#array ) {
    print "$array[$i][0]\n";
}
__END__
abc
def
ghi
[download]

Update: See also How to sort array by columns maintaining the rows? (for C style arrays) and How do I sort a multidimensional arrays?