For food, try using tabelog, which is the Japanese version of Yelp:
http://tabelog.comUsing this site was a huge win for the last time we went to Tokyo. Before heading to a certain area in Tokyo, we'd search for highly rated places to eat in the vicinity. We found many delicious local places that we would have never have found if we had just used some regular travel guides or randomly picked places off the street. I think anything about 3.5 stars and above is safe to try out. There are specialty places for all sorts of Japanese food. Sushi, soba noodles, okonomiyaki, tempura, tonkatsu, kushiage, etc etc. So so good.