Cutstoms - International Mail

I will be receiving my books for my college courses from the US in the mail sometime before August 4. My issue is that I am no longer staying at the address I gave to the school, and it is likely that the package is alreay in Japan.

I need to know if there is a way to stop the package at customs or the post office and physically pick it up myself. Or perhaps a way to notify Japan's postal system that I have changed my address?

Any information that anyone can provide will be greatly appreciated.

Thank you forum readers and repliers.
Okami

http://www.japan-guide.com/forum/quereadisplay.html?0+51916

For other mails as well, you'll need to report your address change :)