First... 1000 miles is roughly 83 miles a month, and just over 19 miles a week. This is completely attainable for most runners who stay consistenty active. Keyword: Consistently. I think consistence is the major key to reaching this milestone. If you get too far behind working towards your goal, you can end up with a lot of "junk" miles that aren't quality that you just throw in to up your numbers and end up throwing off your training.
Second... set your goals in small intervals. You should have, at a minimum, monthly goals to reach (I like to keep these cummulative, so that if I miss a little in June due to vacation, I'm aware that I need to make it up some in July... this allows you to not end up with a lot of extra needed the last months of the year when you are busy with the holidays). Personally, on January 1, I write out a day-by-day calendar for the entire year. It has planned miles (with cummulative goals by week) for all 365 days. Yes, it changes. Yes, I use it as a guideline, not a must... but it keeps my head consistently focused on what kind of miles I should be running.
Third... don't expect to run the exact same mileage every month. We all have ups and downs. In Texas, there are unbearably hot summers... in other areas, unbearable cold winters. There are periods after big races or surrounding big events or vacations where you will need time off... go ahead and plan for it, so you don't feel guilty when it happens. For me, my running peaks March-May and September-November. I put my highest mileage in those months focusing on when my key races are. I allow myself a much easier schedule during the off-months. But I plan for it upfront so that I'm not left doing more miles than I can do safely.
Lastly...be careful. I stayed injury-free this past year. I honestly think a lot of that was due to being hyper-aware of when I needed a break. And there were days I let myself only put in 1 or 2 miles, because in the long run, every little bit helped me stay on track for that 1000 mile goal, but I knew at the time, that my body wasn't up for handling the higher mileage. (Wow, world's longest run-on sentence.)
Good luck on 1000 in 2011!!! Or whatever your goal may be.
Don't forget to sign up for the Run for the Bling of It! 12 races in 12 months, 2011 Challenge.
Don't forget to enter my Mission Skincare Giveaway!!!