how can u change an ip address?

Change public [Internet] address. Depends on Internet Service
=
Reset Broadband Modem: With a straightened paperclip, press RESET button momentarily.
-
Wait 60 secs.
-
What Is My IP Address
- http://www.whatismyipaddress.com

Try to follow steps from http://www.ipaddresslocation.org/change-ip-address.shtml and see of it will help you to change IP address.
If it does not works then it probably mean that your ISP assign to your machine static IP and you can not change it.

Good luck!

You have two types of IP's Public , Private..... Public IP given by ISP , Private IP given by Router.

If you want to change the Public IP you can Reset the router , power cycle it or login to router setup page and renew the IP using graphical interface.But there are two types of public IP's Static and Dynemic ,Static cannot be changed but Dynemic can be changed using the above method.

Private IP can be changed using:

windows 98 http://documentation.netgear.com/reference/esp/wsdhcp/PreparingYourNetwork-3-16.html

windows 2000 http://www.windowsnetworking.com/articles_tutorials/w2ktcpip.html

windows xp
http://www.samba.org/samba/docs/man/Samba-HOWTO-Collection/ClientConfig.html

windows vista
http://windows.microsoft.com/en-US/windows-vista/Change-TCP-IP-settings

windows 7 http://www.simplehelp.net/images/w7tcpsim/index.html

<Option 1>
Step 1: search Google for List of Free proxy server
Step 2: enter your preferred proxy into your browser proxy setting, like IE Go to Tools > Internet Options > Connections tab > LAN settings, then enter your selected proxy address and port
Step 3: search the internet using this proxy, means a different IP address. However, it might not work for all sites, some software and sites still able to identify your real IP though.

<Option 2>
Call you ISP that your want to change your IP

<Option 3>
Change ISP provider

<Option 4>
Move

go to command prompt type ipconfig/all you will need subnet mask gateway and your DNS # also Your IP
then go to network Adaptor double click pick TCP/IP and assign IP address you can only change last 3 # unless you reconfigure your router if you have one or modem or both

YOU CAN"T do that