JR rail passes can be bought at these establisments in the US:
Kintetsu International Express (U.S.A.) Inc. New York 1325 Avenue of the Americas, Suite 2002 New York, NY 10019 U.S.A. TEL (800) 422-3481
FAX (212) 259-9705
JALPAK (JTB GLOBAL TRAVEL INC.) Houston Office 4900 Woodway Dr., Suite 510, Houston , TX 77056 TEL +1 800 776 5575
FAX +1 713 658 1932
JALPAK (JTB GLOBAL TRAVEL INC.) Miami Office 6505 Blue Lagoon Drive, Suite 105 , Miami , FL 33126 TEL +1 800 343 7173
FAX +1 305 269 3013
I strongly recommend buying one of these, it'll cost around US$300, but it'll pay for itself for train travel in Japan.