This advice is geared for the science fiction, fantasy, or horror novelist. I’m going to assume you are serious about your work and want to publish more than one novel.
These days it’s probably easier to get an agent first, because most publishers don’t take unagented submissions. But getting an agent or a publisher is about more than just following the instructions on the website and sending in query letters and excerpts. Why? Understand that the agents and publishers aren’t reading everything themselves. Imagine how many submissions they might get— maybe hundreds a week—and how much work they have to do in order to keep the lights on. So they get interns or entry-level employees, and that’s who does the majority of the reading.
The common term for unsolicited manuscripts is the “slush pile,” maybe because slush is something that in a New York City winter, you just can’t get rid of. The point is, just because the agents you queried never got back to you, or only sent you a form letter, doesn’t mean that your work doesn’t deserve more attention. It means that the system is set up to serve the people who sign the checks, not the people who are hoping for a break.
Publishing is a business, and yet people seem to hold it to a different standard emotionally than any other business. Perhaps because books are special and magical, because they can transport us to other realms, we might not know or want to accept that publishing is a business first. Publishers and agents serve a role in a larger market, there’s competition and trends and trade magazines and trade conferences and printers and distribution warehouses and international rights and a thousand other aspects. There’s the same dependence on trust and personal relationships in this industry that you would imagine exists in any industry. And it’s not personal if a publisher or agent doesn’t like your work or doesn’t have time for your questions. It’s because they have bottom lines to meet.
So your best way through this maze may be to treat it the way you would any career, and network. Do you know anyone vaguely connected to the publishing industry? Could you work with an independent editor who can answer your questions and give advice? Does your local library or bookstore or civic organization ever have authors in to speak? Have you ever taken a writing class? Do you follow anyone in the publishing industry on Twitter? Do you have a local writers group? An online writers group? Are there any conventions in your area, or would you travel to a convention where publishing professionals are? Are you comfortable talking about your book with people you don’t know? If you can start doing these things, finding an agent and/or a publisher will likely feel less daunting.