visiting japan without booked hotel

Im traveling to Japan on a airline staff standby ticket.

On the imigration forms, what do i do about hotel? Does one have to be pre-booked, or can i look for one?

How about booking a hotel which can be cancelled on the same day/1-day advance. Then you can change your plan without paying a cancellation charge. It is better to book a hotel at least for the day of arrival, I think.

to JLady and others: what the poster means is that he is not sure until the last minute to actually board the plane so booking a hotel even for a night is a gamble.
I have the same problem and don't book hotels either as once in a while I can't get on as planned. What I do is enter a hotel name and adress (that I got on the internet and where i would like to go) on the form. I doubt if they have staff who go through all the forms, or even a few at random, and call the hotels....

I think you can book a room at Shinagawa Prince without entering your credit card. However, I think a courtesy email should be sent if you can't make it or give them a call if you decide to stay somewhere else.