Hi Patrick,
I'll third Cello's comment. Nick is up there with Mehran of SoraSound in the audio-nice-guys department.
There are some tidbits about Nick's amp and preamp on my system page. Googling doesn't produce much because Nick is indeed a private designer with no interest in going commercial. Each year he makes 10 or 12 reference caliber preamps (and even fewer amps) for selected clients/friends.
You get selected by being friendly (I lied on the application) and via introduction by an existing owner. Once you learn the secret handshake and unscramble "The Doshi Code" you can join the club.
If you think Nick is hard to research consider Raul's designer. All we know about him is his first name, Jose. Google that!