If you (like me) are new to Steampunk, here is a good definition : "A subgenre of science fiction, it typically (but not always) employs a Victorian setting where steam power and advanced technologies like computers coexist and often features themes, such as secret societies, found in mystery novels."
Though steampunk has been around since the 1980s, (check out these classics) there is a recent crop of exemplary new titles. A personal favorite is Boneshaker by Cherie Priest - a must-read for alternative history fan. It's the 2009 winner of the PNBA Award; and has been nominated for the 2010 Hugo and the Nebula Awards.
Seattle, 1860, rumors of gold, greedy Russians and inventor Leviticus Blue's Incredible Bone-Shaking Drill Engine set the stage for this "impressive and auspicious genre-hopping adventure". When this machine inadvertently triggers the release of a deadly gas that transforms people into the living dead, a wall is built around the uninhabitable city to contain the epidemic. 16 years later, teenage Zeke Wilkes, Blue's son, impetuously decides that he must go into the walled city to clear his father's name. His distraught mother Briar, follows in an airship to try to rescue him.
Boneshaker is exceptionally well written. The plot credibly builds around zombies, steampunk technology, underground societies, mad scientists in a mix of horror/mystery. The fast-paced action is balanced by captivating characters, a strong female protagonist, and tender mother-child relationship. The young courageous Zeke will appeal to the YA crowd.
I first discovered the versatile YA author and an associate editor for Subterranean Press Cherie Priest in her genre-bending adult debut Fathom : a chill/thrill fantasy tale set in her native Florida. Part fairy tale, part modern gothic horror, it had me sleepless for a week.