Next to impossible to get lost in Tokyo, there are so many visable landmarks. There are maps here and there too.
Sushi price varries however an average lunch set at 800 yen gives you this
Spend around 1500 yen and you'll get this
However the lunch sets are a pretty good deal usually 2 options and priced 800 - 900.
(I ordered the rice extra, was only 200 yen)
Decent pad thai in Shibuya, place got packed 20 mins after I arrived.
Of all these were 800 yen lunch sets