If you want to publish a book, you have to be take care of some steps before actually start writing it. There is a good guide at SoYouWanna.com on how the process works. The best way to save effort on writing a book that no publisher (and probably readers too) want is to write a good proposal (very similar when open a new business), find an agent and submit through them to the publishing house:
… The first rule of getting a book published is to avoid writing a book. Whoa, what the hell are we talking about? Yes, it’s very counterintuitive, but the main goal of anyone who wants to publish a book is to land a literary agent, before spending years writing something nobody wants to read. (Of course, if you’re reading this SYW because you’ve already churned out a work of genius, don’t fear; go directly to 2. Prepare a proposal.) Let us explain: the literary world is a very closed community and the people who green light publication accept books only through very specific channels. Think about it: nobody could ever handle reading the mountains of spew that aspiring authors churn out all the time, so the system has established filters to weed out most of the garbage. You need to learn what the filters are and how to get through them. Namely, agents…
So you want to publish a book? – [SoYouWanna.com]
I read an interesting essay by Michael Allen a couple of months ago. He’s a writer and small-press publisher in the UK, and his essay, “On the survival of rats in the slush pile,” is a look at how much chance governs success in publishing, and then offers some strategies for writers, agents, and publishers can use. As a some-day, would-be author, I found it an eye-opener.
The essay is here: http://www.kingsfieldpublications.co.uk/rats.html
[...] So you want to publish a book? [...]
Actually this is a very outdated set of suggestions – apart from the should you do it at all part. Book publishing is not the business it was even four years ago. Conventional publishers are literally five times less likely to be interested in an unknown author/writer who comes without significant automatic sales/publicity built-in. Margins are thin, the business is tough and your chances of success are MUCH higher if you AVOID agents and even mainstream publishers.
Instead research niche publishers publishing in your area of expertise and approach them.
But better yet, do it yourself. You can really truly publish any book yourself (regardless of how well written and edited) for a couple of thousand dollars while retaining all profits (not just royalties) from sales and getting all the ‘real’ things you need like an ISBN number and distribution and being carried on Amazon and so forth.
The challenge is not in publishing – it is in SELLING – and that is why conventional publishers won’t touch anything from you the unknown author.
How do I find an agent for an intermediate-to-advanced level astrology book?