Bzzzzt! Turn that around right now. The only academics I know who are productive in their research and on top of their teaching are ones with defined consulting hours. It takes something of the order of 10 minutes to regain focus after an interruption (if you're interested, I can try to track down the source for this: I read it recently, but that's all I can remember). With academic work, it can be much longer, because of the complexity of the concepts and the necessity of holding so much background in your head to support the concepts.

Think of it like this: there you are, in the warm bath of your academic creativity, when a student comes in and metaphorically dumps you out into the snow. Even after they've gone, and you've climbed back into your warm mental bath, it's going to take a while to get the chill out of your brain.

So set defined consulting times, make sure the students know them, and make sure you stick to them. If they knock on your door when you're working, just don't answer, or answer but tell them to go away.

One other thing that works well is having a bulleting board for questions. Students post their questions to the board, and you set aside a certain time each day to answer them. This way, the whole class (or those who are paying attention) gets the benefit of the question and the answer, and sometimes the students answer each other's questions. It's highly beneficial in the cases I've seen, and can generate a mutually supportive community among the students.

It also means you don't get the same question 200 times. ;)

Spot the mathematician? That's good if you are, because that's where most of my experience lies (that and Comp. Sci.), which means the stuff I've seen working can translate directly.

For now, here's a recommendation: if you're looking first for the practical aspect, start with Section 2. You can read the rest later, and it might even make more sense. I've read the book about half a dozen times now, and I keep getting more out of it, but the nuts and bolts is in section 2.

For the bare bones of time management, try this: block off some hours during your week (as many as you need, if you can get away with that) for research/writing. Use the times when you're at your best, so you're not wasting that prime thinking time on menial stuff. Fit the other stuff around that. Then tweak as necessary as you go along.

If you're interested, I've worked out an incremental approach to GTD: most of my clients can't commit two full days to get set up, then several weeks part-time to implementing and monitoring. So I've broken it down into four stages, so they can incorporate the basics and get those working while they're firefighting, then when they've got those habits they can move up to stage two, and so on.

Exactly. :D