Japan Backpacking -Hokkaido

I am looking for tips and sources of information to plan a 4 to 6 day backpacking trip in Hokkaido during summer 2010.

Shelter. From what I have read on the web and pictures I have seen, there is very limited space for shelters at backcountry camp sites and a tarp with guylines will not work. Will my pyramid fit or should I take a dome tent with small or no vestible?

Bears. The Japanese sources (in English) I have read recommend bells. Do bells really work as a bear deterrent? My experience in Glacier would lead me to conclude they are mostly worthless. Is USA bear spray legal in Japan? Should I take my bear cannister?

Water. What is the best place to go for up to date info on water availability once you have chosen your route?
Thanks