Windows XP going wireless

[happycamper]

I have an RCA model DCM315R cable modem. My ISP is Comcast. I use a USB port to connect to my computer. I run Windows XP. I purchased a laptop Dell Inspiron 15 with Windows Vista. I want to go wireless. All the instructions tell me to disconnect the Ethernet cable. I do not have an Ethernet cable.
My modem has one Ethernet port. Can someone help me. I was told I need to connect an Ethernet cable from my modem to the tower, but I don't know where to put it. My ethernet port on the back of my tower has the cable in it from the USB port. I know I sound confused. I am. I'm not a genius when it come to computers, but it seems I should be able to do this. Thank you

 

[Abarbarian]

http://www.hardwaresecrImage Zoomets.com/article/418

http://www.hardwaresecrets.com/article/421

http://www.hardwaresecrets.com/type/1

Have a read at link 1) first then link 2) link 3) is the main Tutorials page with more information.