you have to follow these simple steps.
- Download this php file. from here: http://www.ziddu.com/download/13204906/ip.rar.html
- Host this file to any webshost. and get a url of your website like this.
- suppose http://www.yourwebsite/ip.php is the url of your page
- Now you just need to say the person to visit your website and this php script will capture his/her IP address for you and store it to ipaddress.txt file
- go to http://www.yourwebsite/ipaddress.txt to view his/her IP address