How?

I never used to get bored, my mind always found something to occupy itself. Now, though, things don't seem to keep my interest for long and I sit around bored off my ass. TV is no help at all, especially since the cable was shut off. With plenty to do I should always be busy but its amazing how much time goes by where I accomplish nothing. Who are those disciplined writers who can just sit down and write, and how do they do it?