Planning to Gifu/Okuhida

I have 4 days off this week and would like to travel to Gifu and see/visit some of the following areas:

Oku-Hida Onsen Village
Kamikochi
Nagoya River
Takayama(if possible)

My geography is pretty poor but I know the above areas are very close together.
Can anyone tell me how I can get to this area from Tokyo? Namely where I should catch a night bus to.

I'd prefer to be based in Okuhida, but I hear it is quite expensive. So should I maybe go to Takayama first (as there is a Youth Hostel there) and go to Okuhida/Kamikochi for overnight stays?

Any ideas would be greatly appreciated.

It is not far enough for night buses. A good order could be:

Tokyo - (bus via Matsumoto) - Kamikochi - (bus) - Okuhida - (bus) - Takayama - (bus) - Tokyo

I am not familiar with "Nagoya River".

I recommend to spend one night each in Kamikochi, Okuhida and Takayama.

Kamikochi:
http://www.japan-guide.com/e/e6040.html

Takayama:
http://www.japan-guide.com/e/e5900.html