If that is a 2x4 tent, then I personally believe that 2000w light for such a small area is complete over kill. 3 plants gonna over run the tent if they grow as expected. You can always try a scrog grow as well.
Check out the Autocob from
www.cobshop.net. I own 6 and they are great lights with no fan noise, only .49 amp draw, small and easy to move, low heat throw.
Regarding clip on fans, there is a type available that will clamp to your tent poles. They are a little more expensive, but the convenience they carry makes it worth it for me anyway. I just hope the quality holds.