I will always try and contact a personality if I can, no matter how remote the odds of them accepting are. It took me over a year to track down and convince Tom Kalinske, and I had to hound Yuzo for a little more than that (he was really sorry about that though, and he sent me some autographed soundtracks!). Japanese personalities are just not as eager to talk.
Case in point: I just shot off an email to a mutual contact I have with Shuji Utsumi. I got shot down because Utsumi is very private and doesn't talk to journalists.

Unless a friend of mine bumps into him at the Tokyo Game Show or Game Developers Conference, he won't be talking.