1. use strictures (use strict; use warnings;).
2. $self->{i}={[(110,FB),(100,F)]}; does not make sense. What do you intend?
3. Where are you looking to return a hash value?

The following reworked sample code may give you some hints:

use strict;
use warnings;

package ngetlogstdin;

sub new {
    my $self={};
    $self->{o}="ngeterr.log";
    $self->{a}=undef;
    $self->{i}={110 => 'FB', 100 => 'F'};
    $self->{F}=undef;
    $self->{B}='http://wibble.wobble.com';
    bless $self;
    return $self;
}

sub access {
    my $self=shift;
    my $arg=shift;
    print $arg; # Note that "result" of print is the return value
}

1;

package main;

my $obj=new ngetlogstdin;

for my $key(keys %$obj){print "$key\n"};

my $arg='tomatoes';
my $value=$obj->access($arg);

print $value;
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Prints:

F
a
B
i
o
tomatoes1
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