Problem--no, ADDICTION

I have many additions.
The list starts with chocolate, candy and other sweets; television; checking my e-mail (which I do literally five times per day...I know, it's that bad); Christmas; watching the same movies over and over again; and the list stretches on for miles. These don't seem so bad, because they're just things that people can normally get hung up on. They're completely innocent, as long as they don't "out-balance" the other parts of your life.
But the worst addiction I have is...well, I guess I shouldn't call it an addition, it's more of a serious problem..My biggest problem is that I get so distracted from doing homework when I'm at my desk (or anywhere for that matter), that sometimes I end up not doing homework at all- even after spending three hours in my room with textbooks open and papers lying all over the place.
I should/want to blame it all on my computer, since it always sits at my desk with me...so it's very easy to get off track of my homework as I randomly decide to check my e-mail and Facebook accounts. Every time I surf the web, I tell myself that I'll get back to work in five minutes...But I always end up looking at the clock with having had half an hour or even two hours pass by!
This serious problem can probably be considered as an addiction, now that I think about it, because for months I've kept promising myself that I wouldn't touch the mouse or keyboard anymore when I sit at my desk, or telling myself that I won't do anything on the computer until I've finished my homework...But these have never been able to conquer the temptation that lets me drop everything and jump to the easy route of avoiding the work.

I don't know what to do besides to just keep on trying to resist the problem-no, addition...?