Johannes Cabal the Necromancer by Jonathan Howard is pretty hilarious mashup of Faust, Wicked and Something Wicked this way Comes.

Cabal has long ago sold his soul to the Devil in exchange for sorcerous power but discovers that the lack of a soul is interfering with his experiments. So he travels to Hell in order to retrieve his soul from Satan, who not unsurprisingly takes the viewpoint that a deal is a deal.

Nevertheless, since the Devil is nothing else if not a greedy sort, He agrees to return Cabal's soul to him if Cabal can , within one year entice another hundred people to sell their souls to the Devil. In order to assist with this the Devil gives him an enchanted carnival.

Of course both the Devil and Cabal have some hidden interests. It's a fun read. Cabal is assisted by his older brother,Horst, who Cabal accidentally turned into a vampire in another experiment gone wrong. The book is written in a very sardonic tone, not unlike that of Terry Pratchett or Simon Green but is a little darker. Cabal is a self-centered, egotistical, immensely practical man who doesn't suffer fools lightly.