Almost all broadband service providers will assign your computer or home network a "static IP" address. If you're connected to a broadband network and need to change your IP address I would suggest contacting your broadband provider.*EDIT* - There are a few ways to change or hide your ip without calling the cable company. They are spelled out here:
http://hideipaddress.net/hide-ip-add...ddress.htmlThe best way to hide it is by proxy. There are several free sites available, but know that your surfing speed will decrease drastically. There is also a program called tor which will hide your ip:
http://tor.eff.org/Hope that answers all your questions.