I finished my 1st draft of my 1st book in the Spring of 2010. I sent it off to 3 different publishers that summer, and 2 of them were interested but suggested a few changes before they were able to publish it. It wasn't until 2 years later (after having some beta readers read over my book & I made massive changes) in the Summer of 2012 that I signed with Walnut Springs Press. Since I was a new author, my book got on the wait list until the Fall of 2013. After edits, etc, it was in stores and available on Amazon December of 2013. So, from start to finish - it took 4 years (that's including the time it took it write the 1st draft).
My 2nd book was a lot quicker - especially since I had already published. I finished the 1st draft in the summer of 2015 and it was in stores December of 2015. From start to finish - it took 1 year.