Short answer: dont do (try) it, too much hassle.

Long answer:
The drop bar wont exactly be a problem. You may need a new stem to accommodate however. As for your controls, you are looking at new brake levers and of course new shifters.

The problems start when trying to find drop bar brake levers with appropriate amount of cable pull, that will work with the V-brakes that you currently have on the bike.

As for the shifters, you will likely have to fab some type of downtube-mount system to hold the shifters. This wont be the easiest or prettiest. For hints on how to pull this off, check out some of the pictures from events such as krankworx or other jump/slopestyle events. Occasionally some riders will mount shifters to the down tube, to allow for bar spin tricks.

If it were me, I would forget about making the swap on your current bike and finding a new (to you) bike that already has the downtube shifters installed from the factory. Additionally, older bikes like you will be looking for will more than likely have drop bars on them already.