My friend helped to edit the Eater guide to Tokyo earlier this year so it's quite good.

https://www.eater.com/2017/2/21/14652924/tokyo-best-ramen-su...

As for sushi- there are a lot of good places near the Tsukiji fish market. There are cheaper places and more expensive places- you can walk around and look at menus and decide. Some are kaiten, some are not. Near the fish market, you generally get what you pay for- which is to say that you can get a good sushi meal for 5000 yen, a very good meal for double that, and if you want to pay more, you can get much better than that too. In general, the top places are not near the market- they're in Ginza or other neighborhoods.