ride and Prejudice was published January 28th, 1813.
Doing some wiki-style digging, I discovered that Pride and Prejudice was originally completed in 1797. Jane Austen let the manuscript sit a while, then came back to it, revising it and sending it off to the publisher again for publication sixteen years later.
In a world where Harry Potter came out every year and Stephen King finishes a measly two books a year, I’m glad to see that, historically, I have something to point to. Julia was started as a Nano in 2005. I came back to it in 2009. Not quite a 16 year hiatus, but enough time that I was starting to wonder about my commitment and ability as a writer. However, Austen did finished the original manuscript and her revisions in one year (again, according to Wikipedia). I’m slipping in that regard.
While I look to Jane Austen for writing advice, Suzannah at Write It Sideways explores what the characters of Pride and Prejudice can tell you about writing.
The Empty Pen 
I was just talking with a friend about how quickly academic and theological studies are coming out [in book form] about the Twilight series. Even for Harry Potter, the actual books that ‘studied’ them were several years in coming.