Kelley Armstrong: Industrial Magic [2004]

After Paige Winterbourne is ousted as leader of the American Coven of Witches, all she wants to do is hide under her duvet for a few months. Let the supernatural world manage without her, see if she cares...But fate, of course, has other plans. A murderer is on the loose - someone with superhuman skills. When Paige learns that the killer is targeting children, she realises she has to get involved in the covert investigation. And so Paige - desperate to protect those she loves - is thrown into a world of arrogant Cabal leaders, drunken necromancers, sulky druid gods and pretentious leather-clad vampires. Luckily, she has a female werewolf and a certain renegade sorcerer on her side...