Also, just curious, what is considered an average number of copies of my book that the publisher will print? And do I get any of those copies free? Or do I have to go to the store to buy them like everyone else?
Like word count, this depends upon the type of book. It also depends on things like how confident your publisher is that it will sell well, how much money they have to invest in your project, how energetic you are about marketing and promoting your book, how many pre-release orders they get, how the industry is doing, whether they print in the USA or overseas, which way the wind is blowing that morning and whether or not they’ve had a recent fight with their spouse. (Oh, no. Strike those last two.)
For the LDS market, an initial print run on a new book/author is 2,500—5,000 copies, although this does vary between companies. If you’re a big name (like a prophet), the first print run is probably closer to 10,000, maybe more. If your initial print run sells through quickly (in the first 3 months), then the next print run could be much higher.
Most companies will give the author a certain number of free copies, then allow you to purchase additional copies at a wholesale price, which you can give away or sell yourself. The terms and conditions for purchasing and reselling your own titles are usually spelled out in your contract. You should never have to go buy your book at the store.