Here is a quick solution written in php that you can use to determine the current IP address of a given webhost/domain.

ip.php

<?php
echo GetClientIP(true);

function GetClientIP($validate = False)
{
    $ipkeys = array(
        'REMOTE_ADDR',
        'HTTP_CLIENT_IP',
        'HTTP_X_FORWARDED_FOR',
        'HTTP_X_FORWARDED',
        'HTTP_FORWARDED_FOR',
        'HTTP_FORWARDED',
        'HTTP_X_CLUSTER_CLIENT_IP'
    );
    
    $ip = array();
    foreach ($ipkeys as $keyword)
    {
        if (isset($_SERVER[$keyword]))
        {
            if ($validate)
            {
                if (ValidatePublicIP($_SERVER[$keyword]))
                {
                    $ip[] = $_SERVER[$keyword];
                }
            }
            else
            {
                $ip[] = $_SERVER[$keyword];
            }
        }
    }
    
    $ip = (empty($ip) ? 'Unknown' : implode(", ", $ip));
    return $ip;
}

function ValidatePublicIP($ip)
{
    if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE))
    {
        return true;
    }
    else
    {
        return false;
    }
}