An author "voice" as I try to explain it, is kind of like an accent for your book.
Imagine a southern drawl, or a wicked good east coast vocabulary. You know that even though someone from the south and someone from the northeast might have the same speech to convey, the two of them will have very different word choice and sound. Now imagine those same people were writing books. They would have their own slants on the storylines, and their own takes on current events framed around the culture and demographics in their areas. They would tell the same story from different view points, with different words, and focus on different subplots. They would have a different voice.
The way I write a book is very different from the way others write books. I love reading good BDSM books, and am intrigued by the power exchange and great communication that happens between the couples. But when I take my snarky joke-loving writing style into a book...well...let's just say it doesn't work. I tried it and I learned quickly that I shouldn't ever write BDSM. My characters were laughing at each other instead of getting it on.
How did I find my voice? Reading. Lots and lots of reading. And after that? LOTS AND LOTS OF WRITING. And this isn't writing that has ever or will ever see the light of day. This is writing I did to get my style under my fingers. I don't even remember how many nano novels I wrote under my old persona before I switched my account to my pen name. (I'm Roxy Mews on the NaNoWriMo website if you want to buddy up this year.)
And here's the real kicker. I'm not sure if you can teach voice. Voice can definitely be developed, or edited out of a manuscript if a new writer encounters a bad editor. My voice has changed from my first book to my current WIP. Mainly because my voice is me. I've changed a lot in the last few years. So my work will have a different accent now. That's not a good thing or a bad thing, but you'll be able to see a change in what I'm writing.
I found this video by a YA author, and while I'm not in agreement with all her videos, I do think this one on voice is pretty spot on. And she chats about "Teen Voice" and "Character Voice". Each corner of the fictional genre market is going to have a different tone. And if you don't match it, or do something completely different because you're not familiar with it, you're likely to alienate readers. (You can check out the sales on my #ROBOSEX books for a prime example of that. I don't think my voice works well for the Sci-Fi market. But I still love the books, so click over on the side bar if you want to read about a sexy nonagenarian's adventures.)
Anyway...check out this video for more info on "Voice."
Do you have a strong grip on your own author voice? Or are you still looking for it? Or do you have a totally different view on "voice" than I do? I'd love to hear about it.