Currently Being ModeratedNov 25, 2012 9:12 AM (in response to Dan Perkins)
Hopefully someone with current Japan telecom knowledge will be able to give you more specific information from my experience of global travel (if you don't want to rely on wifi) is - get an appropriate local pay as you go SIM - obviously you need to ensure that your iPhone is unlocked.
Even if its not unlocked a cheap local handset is often (depending on the duration of your trip) MUCH cheaper than roaming charges - particularly the data hungry iPhone!
Good luck ;)
Currently Being ModeratedNov 25, 2012 9:14 AM (in response to Dan Perkins)
You'd be best off calling AT&T. They can explain all the global pricing options they offer and help you set everything up. They will need to enable your phone for global use.
Note: free WiFi is not nearly as common in Japan as it is in the U.S. so you're wise not to rely on it.
Best of luck.
Currently Being ModeratedNov 25, 2012 9:16 AM (in response to Dan Perkins)
Sorry should have added - Check also with your carrier - they could have a roaming plan that could work out well