Yahoo Finance lists the major currency mid-point cross rates, with $/ ¥ at the top.


The Tokyo Mitsubishi UFJ bank rates are the ones listed in most newspapers here, and show you what you will get at the banks.
Although the webpage is in Japanese, it is easy to understand.
For those unfamiliar with the terminology:
TT is Telegraphic Transfer  ( the rate for money wired bank-to-bank ) and is also the rate for travelers' checks.
S is the Selling rate and B is the buying rate.
As you can see, the spread between buying and selling rates for cash is always rather larger than for TT transactions, especially for currencies other than the US dollar.
Generally speaking, you will get the most Yen for you dollar, pound or euro by bringing travelers' checks.