Ok, I took the plunge and bought up all the requisite elements from ebay to make this work. I have an i605 phone (as suggested here) and followed these instructions.

But as soon as the phone says that the n800 is connected, it then says it is disconnected. And the tablet says "Internet connection Failed."

Any and all help is much appreciated (as was the idea in the first place)! I know nothing about this phone (just got it today), so maybe there are some settings I need?