Nope, no printed "Night" domain for 3.x D&D as far as I could tell. Just Darkness in the FRCS and Deities & Demigods (the latter of which got its crunch added to the SRD after a while).
There's a Dragon Magazine issue from around 2004 with darkness as a theme, and an article on Erebor, a god of darkness and shadows, but no Night domain; Erebor just had the Darkness domain. That issue had stuff like darkness pseudo-elementals (or was it shadow pseudo-elementals? whatever), dark ones, some spells using the Plane of Shadow, and a bit else related to the theme.
Exception: That realmshelp page Dandu linked to apparently has a Night domain, but I have no idea what the original source was. And realmshelp is just a pile of stolen non-OGC rules material from various books, without sourcing or permission as far as I can tell, so that site's more or less the same as pirated material. Which I hate with a passion.