This isn't a plug--the site is totally free.

"You can do anything for 15 minutes." --FlyLady

Get yourself a timer and just do it for 15 minutes and no longer. Just concentrate on that one thing until the timer goes off, and then make yourself stop. If 15 minutes is too long at first, try 5. You will be utterly amazed at how much you get done in that little bit of time. The key is to focus on that 1 task for that amount of time and then make yourself stop.

I'm sorry offering up a simple solution seems so mundane. I guess more prolific procrastinators than myself would prefer to discuss it ad nauseum instead.