I'm arriving in Tokyo on Saturday afternoon, Sept 8. Should I simply go to the ATM at Narita Airport? Are the rates inferior at all ATMs? How much worse, if at all, at the airport? After that, where is the best place to get yen for the best rates? ATMs? Banks to exchange dollars? Credit cards these days charge 1-3% just for using them, aside from the exchange rate. Any advice appreciated. Thanks!

Usually you get the best exchange rate at an ATM unless your bank has a high service charge...

After that you can get yen at post office ATMs.

Also now the 711 stores take foreign ATM cards but there may be a small service charge for that.

At Narita, there are Citibank ATM that should work with non-Japanese cards with Cirrus or Plus network logos. Just make sure you use bank cards and not credit cards.
I haven't used the exchange desk at the airport (there is one before exiting the customs), but ATMs should use the same rate regardless of the location.
I found ATMs at many banks didn't work with non-Japanese cards, and mainly used 7-11 convenience stores (most have an ATM terminal inside the store).

Since I didn't want to incur per-transfer charges, I carried much higher amount of cash (say, JPY100k) than I would normally do at home.

Thank you for that info. So just to be clear, the exchange rate for cash is the same as in the ATM? And the only downside to the ATM is the transfer charge from my US Bank, right? thanks

The downside is your bank fee(s). The upside is the better rate.

I guess it depends on your bank. Mine doesn't charge anything. I have checked their exchange rate, and it was within 1% of the foreign exchange bank rate that day.

Does your card have a Visa logo, Mara?

mrwunrfl, no, I have the old fashioned ATM card, not a debit card. I am afraid of them ;-)

I used the interbank rate on oanda.com to check the exchange rate my bank gave me.

Check cards with a Visa logo charge 1% currency conversion fee. Even with that, though, it is better than exchanging cash.

Yes, my bank's debit/MasterCard will charge 1% on every transaction (plus $2 every time ATM is used). So, are you saying that the exchange rate at the ATM is still better than exchanging US Dollars somewhere? Thanks! Leaving tomorrow!

Yes, that is what I said, what I believe.

I do what W9London suggested and get a bunch of cash (at the Citibank ATM).