I was thinking a good fit with some of the horror and humor of the Dresdenverse would be Whedon's Buffyverse.  I have used a Harry-style character in a Buffy campaign I ran.  I was think of using some stuff from Buffy episodes as inspiration for Dresden adventures.  One ememy I was thinking about would be the Gentlemen from the episode Hush.  Use them as a group of wild Fae like the Erlking from the Nevernever that comes to town to cause havoc.  Maybe a wizard has summoned them as a diversion.  Maybe they are looking for something or someone.  maybe one of the PCs.

I do not know the group I will be using as PCs.  I was thinking of just letting the players think up individual characters with no overall theme because I do not live in a city with enough interest to have a large group of wizards or anything else for that matter.  I will probably just end up using Baltimore.