Not unless you force them to enter details about themselves before asllowing them access.
The best you can do is to track which ISPs your visitors use based on the IP addresses that they assign to your visitors. To be able to track this you will either need access to the server logs or will need some form of counter on your page that records that information.
Yes you can do it for 15 days free of charge. Use a program called web ceo (which itself is free of charge) and then apply for the tracking thing for free!!! It's soooooo cool! I use it aswell. The actual program is for getting your website to appear further up in search engines with again can be very useful! Try it!