@xxsl1kxx: To add to the above, you simply can't "fake" your IP address when communicating with another host, all you can do is redirect the connection through an intermediate third party. With the correct privileges on the system you can send out an IP packet with a different source address, but the other end will send replies back to that incorrect address so you'll never see them. Because HTTP runs on top of TCP, and that relies on getting these replies, then it just won't work.
In principle if you're using a connectionless protocol like UDP then you can lie about your source address, but it's a really underhanded thing to do and may be regarded as an attack of some sort by other sites.