It is hard, especially when Dresden is jokingly referred to in some circles as "the other wizard named Harry" not to draw parallels with Harry Potter. I even use that as a selling point with people I know are fans of the latter (and I do try to sell it to anyone I can). But for those who are not, don't let that sway you. The Dresden Files has enough of its own merit to stand alone but the parallels are there, should you chose to draw on them. Both are orphans who found out about their magical talent in adolescence. Both have god parents who figure heavily into their lives and into the story lines. Both answer to a higher governing body of wizards with their own set of rules outside those of "normal" society. Both find themselves pursued and persecuted by that same governing body. What makes these parallels even more interesting is that Butcher and Rowling started working on their series on separate continents at roughly the same time so the similarities are, for the most part, coincidental.
At its core, The Dresden Files is a slightly off-noir, first-person narrative, detective series. Harry is a wizard-for-hire with a P.I. license, consulting for the CPD; he finds missing people and things. The major difference is sometimes the bad guy on the other end is a for real ghoul, not just a metaphorical one. If you like your urban fantasy fast-paced and sarcastic, or your detective noir supernatural and sarcastic, The Dresden Files is a must-read. It is the mark of a good book, in my opinion, when you startle the people of Starbucks because you actually guffawed into its pages. And I have done plenty more than that on more occasions than I care to admit.
Thirteen full-length installments of The Dresden Files, as well as various short stories and graphic novels, can be found in hardcover, paperback, e-book and audio formats wherever these are sold. The fourteenth of the series, Cold Days is due for hardcover and electronic release in November of 2012.