Here are a few interesting Nixie Links...

Onno Massar's Neon Nostalgia
Alfred Apperloo (in Dutch language)
Mike's Nixie Gallery
Ask Jan, a great Nixie Tube source
Sphere, another great nixie source
Dieter's Nixie Tube Link Page
Linux Software Nixie Clock
Klokworks

If you want me to add a link, just email me...