To be a touch more practical (added - I see Dev we are on the same page - www.krtraining.com
in our area):
1. What area of the USA are you willing to come to?
2. Check out local laws about noncitizens or nonlicensed folks handling firearms. Some states may have prohibitions, many do not.
3. I have heard that Japanese tourists visit the West Coast and Las Vegas and ranges have special tours/classes for them.
4. I know in TX that we have hosted Asian visitors from China and the Middle East at our matches and clubs without difficulty.
5. It can be done - there are Japanes airsoft shooter clubs. A young man came here and shot normal IPSC and was very successful. Perhaps you can contact the Japanese IPSC for ideas - http://ipsc-japan.org/
6. Same for IDPA - http://www.idpa.com/clublist.asp?pick=Japan
Give us a hint about where you want to visit and we can help you contact reputable schools and they probably have a handle on laws and arranging visits.