This may sound archaic to say, but I would recommend searching for an agent before searching for a publisher. (Unless you already have an agent). With the ease of self-publishing these days, a lot of writer's are forgetting the traditional channels for book publication. The first step is finishing the book. The second step is writing a query letter and summary. The third step is submitting to agents. Getting an agent will have someone in your corner who knows the legal mumbo-jumbo and WANTS to see your book published. They also have connections to get it onto the desk of the publishing company that really matters. They don't charge up-front (so I'm told), but rather represent you based on their personal faith in what you've written and its marketability. Then, after it is published, they get a percentage of your profits.