Maggie Griffin told me to read Jim Butcher. When Maggie tells me to do something I usually do it.
I proceeded to get all the books, the first six are paperback originals, the latest two are hardcover.

And I love them.
Dresden is a PI in Chicago, working with the Special Crimes Unit.  He’s also happens to be a Wizard.
And a  bit of a maverick wizard at that. Spending most of time on the outs with the wizard council. That makes difficult cases just that much more difficult. Mix crime and the supernatural, add a wizard that’s all for Justice but really likes to break the rules, and you’ve got The Dresdon Files.
These books have all the classic elemants of great PI books, and the supernatural elements really makes them fun and unpredictable. They are being turned into Television fare by the SCiFI channel.

I strongly urge you to try them out.
Jim Butcher’s Website