It is impossible to prevent access to the IP address to hundred percent. The most advanced hackers and the most secret intelligence agencies do not manage it even. But if the ordinary user has nothing to hide, then competently to be protected from the accidental attacks quite perhaps.
1. If you work in the local area network, configure the proxy server so that your computer contacted external resources only through it. The external users wishing to get access to your IP address will "see" only the proxy server. However to be protected from the foes working with you in one network you should resort also to other methods.
2. Limit also access from a local area network to external. Prohibit visit of certain websites. Install the phishing filter. Acquire the antivirus software and powerful Firewall.
3. Enable protection against Java scripts, having limited their access to any given opportunities of your browser. One of the most reliable options – a total ban of execution of active scripts. But, working on the Internet, from the Java language, and not just scripts, you will not be able to be protected as it has a huge number of network functions. And meanwhile, programs on Java can calculate your IP address without problems.
4. Prohibit ActiveX, and automatic installation of plug-ins. Always check plug-ins before their update. Buy the program-soksifikator, do not download it free of charge from the unknown websites. Otherwise all your protection will work against you. Before each session check the proxy server according to "black lists" (RBL) that your real IP address was not defined.
5. If you are connected to network directly, regularly clean Cookies, and prohibit them better. It will also help to protect the IP address, and will allow to optimize operation of the browser. However it can complicate work with the websites work with which requires input of the login and password (and them much). If you use ICQ, select the checkbox prohibiting to show the IP address in settings. Regularly contact on the official site of vendor of OS which is installed on your computer, and download patches. The antivirus and Firewall, undoubtedly, too is required to you.