The printing rooms are called "Darkrooms" and are in fact painted bright white.
Most rental darkrooms are listed in the "yellow" section of the phone book. You can also check with some local schools that teach traditional photography and ask them for ideas.
What I do from time to time when I need to use a darkroom, I attend a class at my local community college which gives me access to the darkroom nearly 12 hours a day six days a week.