The address of the Firehouse is revealed on the vacation invite: "3960 Ince Boulevard New York, NY". The post date of the vacation invite is November 4, 1997.
Lilith received an entry in the 2016 tie-in book "Tobin's Spirit Guide - Official Ghostbusters Edition" on page 60 and 61, where it is identified as a Class VII: corporeal, affinity with electricity, parasitic.