Hi. Can anyone tell me what's a good time frame to prep for Step 3? I won't receive my ECFMG certificate until January 2012 so during the time being I would like to study for Step 3. When should I start? Should I start now? Or wait a few weeks? I plan to read first aid and master the boards and do UW questions for the exam as well as take some NBME. Would that be sufficient enough to do well on the exam? Thanks ahead of time.

I think you should start now. If you get ECFMG certificate in January 2012 , you can also have step 3score in hand at that time! That will be great to have in case there are post match positions and if you still can get interviews in jan.
About the step 3, I am doing Archer review course, UW, master the boards. I am planning to take NBME may be a month before the exam. Where are you located?