Access: For access please refer to the J-PARC access information:
J-PARC access information. (Note: you should be reaching to the dormitory -- the meeting venue is within a few minutes walk.) The easiest way to reach Tokai station is the Airport buses, but the trains are also very straight forward. From Tokai station, you can use a local bus (~12 buses every day) or taxi. Also, the organizers may be able to pick you up at the station, if someone is available.
Immigration/VISA: Most western countries are exempt from VISAS for short term visits (up to 90 days) for tourism or business. All you need is to fill out the landing form in-flight and have a valid passport. You need to state your address which is for most: 203-1 Shirakata, Tokai-mura, Nakagun, Ibaraki 311-1195, Japan.
Further information about Japan (Tourism, access, etc):
Japan-Guide
