The internet is a conundrum for modern writers, because it's our primary source of readers and our primary source of distraction. Writers have to learn to use the internet without letting it swallow them whole.
So how do you stop yourself from frittering away your time checking your email, or visiting Facebook, Twitter and a zillion other sites specifically designed to distract you from your primary creative work?
One idea: use it as a reward. I make sure the first thing I do every morning--before I open up a browser, before I check email, before I check anything--is write. I write for a minimum of 30 minutes, but preferably an hour or more. After that, and only after that, I'll reward myself with the right to open a browser window and surf the web.
But this still leaves a door open to waste time, doesn't it? So, before I start surfing, I set a countdown timer to 20 minutes. In those 20 minutes, I batch process my emails and then use whatever time remains for undirected newsreading and websurfing.
When that timer goes off, I might stall for just a few more minutes (hey, I'm only human!), but then I'm usually pretty good at getting right back to my writing and research. The point is to give yourself some time to goof off. Then, get back to work.
This simple technique has saved me untold hours. Try it.