Beating internet addiction

Ok, so basically for the year or two, I've been suffering from a problem and I don't know what to call it - let's just say internet addiction. Basically, I could be on the internet for up to 7 hours some days, and often even more. It is really interfering with my life, my studies in particular. Does anybody else find themselves in this situation, aka. wasting half the day on the internet, and if you were before could you give me some tips on how to get over this and cut internet usage down to a healthier 1-2 hours a day?