What is wrong with the spam on my computer???!? It's out of control!!! Please help!!?

[Ned]

This only started a few days ago, but no matter what browser I use, there's nothing but spam! Everywhere! Even Wikipedia is FLOODED!!!! Every site text has links to spam websites straight from the text! I downloaded multiple malware/spam control programs, including Malwarebites and Windows Virus Control, and it says my computer is clean. I've even ran full scans, taking up to an hour. Every time I open up the browser, Malwarebites blocks so many pop-ups its not even funny. The root of the pop-ups are all from the same IP Address. I've tried changing my IP Address too..... not sure if it worked, but that's not helping either. Please, someone help!!! I'm worried I'm being tracked by some creep or something!! Also, if it's any help, I've been using FireFox, Google Chrome, and Internet Explorer..... I had to get three different browsers just to attempt to stop the spam!