As mentioned, the Deadlands line is a
great resource; I don't reference the Western genre without it.
As for who is around, yes, the Council, the Denarians, and most of the Old Guard Wardens (including Luccio). The Raith family is obviously around, and relatively old (and by the comments Lara made in Turn Coat, I'm guessing she and Luccio met in the late 1700s). I wouldn't doubt Ortega would be around, as well as Arianna, and I'm with the others in that while there isn't a war, they would still be actively causing problems (especially with the issues between the U.S. and Mexico).
I also think that many of the biggest hitters of the White Council, Black Court, and possibly even White Court would still be in Europe, though. Remember the Stoker's Dracula won't be published for another twenty years, so the Black Court could quite possibly be the biggest supernatural threat, especially with how easily they can "reproduce."
I would suggest looking into Native American mythology/folklore, especially of the tribes that may still remain in that area at that time. One idea due to what I have posted below, the other in reference to a slew of "monsters" that may have still been prevalent until they were hunted and wiped out (akin to Dracula and it's impact on the Black Court, only with the prevalence of firearms, electricity, etc).
Or you could pull a page from Deadlands and have a renegade "tribe" of "Lost Sons" who wish to strike back at the White Man by any means necessary. . .including summoning an Outsider (whom they see as an ancient spirit, ancestor, protector, god, etc).
The following section is going to have some references to both Turn Coat and Changes:
I can see Skin Walkers and other Native American "legends" still being prevalent in this time. Sure, the Native Americans were getting shoved into reservations and away from their usual lands, but I can see some old legends and creatures still holding power.
I reference this primarily because of Changes; the Gods of Endless Night were just Red Court Vampires who were very old and praised as Gods; who is to say another entity that was praised/revered by the Native Americans wouldn't reach a similar status but steadily lost power as the faith and member base was slowly being degraded, shattered, and destroyed?
Again, just a few ideas. I hope that helps a bit!