The NIT CAN indeed supply power over its USB connection, it is however limited in how much it can put out - 100 or 200 ma max, I forget.... This should be enough for a flashdrive (mine works), but not for things like a (non-powered) Hard Drive, or something. Also, the hubs take power to run...

I think that the problem you are having is that you are hooking the hubs up the wrong way, so to speak - there is only one connection that is designed to be connected to the computer, and it will not (I do not believe) work if you connect to one of the 'inputs' -- for this reason I do NOT think your 2 hub strategy will work (I could be wrong).

What I did, is purchase a USB Female A to Female A adapter on amazon.com - it is only $1 - $2, I believe, and it slips over the end of the cable you already have to give you a single usb port. Use the software you already have to enable Host Mode, and you are ready to go. If you need to hook up more than one thing at a time, then get a hub (powered would be best) and hook it up to the adapter instead (either way, you need an Fem A - Fem A adapter).

Alternately, you could buy the OTG adapter mentioned above - it replaces the FemA - FemA and stock USB cable I use, with the added advantage of switching automatically (no need to switch modes in software).

Hope this helps,
Patrick