Let's see... Many of the books I'm suggesting (not necessarily recommending) I haven't yet read - I just purchased them to read and haven't made time. There are also a few that aren't technically steampunk, but I'm passing along as recommendations anyway because they are close in theme enough you may enjoy them regardless.
Chenda and the Airship Bofman by Emilie P. Bush
^ This is a book I purchased at an Atlanta convention directly from the author, who seems to dress steampunk in daily life. A quick glance at Amazon reviews are all positive and I was very impressed with her when speaking with her.
There is the "Monster Blood Tattoo" series by D.M. Cornish, "
Foundling" and "
Lamplighter".
^ A pair of books I've heard extremely good reviews of, but haven't yet read.
Airman by Eoin Colfer
^ Technically not "steampunk", but on-theme enough I consider it so regardless. This one I
have read several times and enjoyed. It has a flavor of The Count of Monte Cristo (one of my absolute favorite books).
Airborn by Kenneth Oppel
^ Again, not technically "steampunk" but more-so than Airman as I believe that it is closer to intentionally so. Also a book I can personally recommend from having read and enjoyed. IIRC, it also has a sequel, but I haven't read it yet.
There is a series called "The Society of Steam" by Andrew P. Mayer I saw in a bookstore while I was in Australia. I wrote the series name down so I'd be able to find it again. The first book is "
The Falling Machine" and seems to have good reviews on Amazon.
Now we're getting into recommendations I can make, but am not sure you're really looking for.
There is the Temeraire series by Naomi Novik, which starts off with "
His Majesty's Dragon".
This is
not steampunk really, but I suspect you may just enjoy. The premise is that dragons exist in the world and in the Napoleonic Wars (early 1800s) they were used essentially as airships for battle. It is more "alternate history" than anything else, making use of real historical figures and their real battles - they just have air support that they didn't in reality. I enjoyed the first few books, but got sort of out of the mood during one of them and will have to start over since it's been so long since I read them. Reading it was a bit like reading some of the war novel series my dad used to read, so I even recommended the series to him. (The fact that he was named after one of the real life navymen mentioned in the series helped.)
And of course, there is a series I recommend in hesitation as I'm not quite sure you would have any interest in it, but I figure it's safer to do so for completion's sake.
Sorcery & Cecilia or The Enchanted Chocolate Pot by Patricia C. Wrede & Caroline Stevermer is the first book in a steampunk-lite series. Granted, it's set mainly in the Regency era (same as the Temeraire series) rather than Victorian and it's more magic than steam, but it's an enjoyable series, though perhaps more romance and magic than anything else.
Looking at the Amazon suggestions for some of the books I recommended, it may be doable that you'll find other books in the genre that you'll enjoy. And of course there are books like H.G. Wells's works that inspired the style. I found this link that also gives what look like good recommendations
Twenty Must Read Steampunk Books – An Introduction to the Genre | The Ranting Dragon (Though their final suggestion of
Howl's Moving Castle is a good suggestion as it's a good read, they underplay how much more steampunk the anime version was than the source book. And I admit to preferring the anime adaptation overall.)
Hope these help. :3
