That gives you two choices: find an agent or approach a publisher directly. Different authors have varying opinions on which path is better to take. One of our sources, a prolific novelist, says it's often better to go directly to a publisher if it's your first book, because it's so difficult to find an agent you can trust. Another, a non-fiction writer, contends that most publishers use unsolicited manuscripts to line their bird cages.
What they both agree on is the value of the Writer's Market, an annual publication that gives the lowdown on just about every book and magazine publisher in the country (the areas each publisher focuses on; contact information; what type of paper to use). It also contains an overview of the market in general, helpful advice, submission guidelines, pay rates and information on royalties and advances. It's important to determine which publishing houses are most likely to take you. So do your homework - go to the bookstore and find books similar to the one you've put together. Determine who publishes them, then call the company and find out who edited them. Pick up the Writer's Market (or check it out of the library) to find the contact information and write to the editor directly, explaining why he or she should be interested in your work.
Put together a business plan, treating your book like a fledgling business. In the plan, you should show that you've done your research - describe the market for your book, list existing books that are similar to yours, and specify why people are going to prefer your book. Your plan should also contain a summary of what your book is about, complete with a sample table of contents (where applicable) and two or three sample chapters.
~If you decide to find an agent first, you have to make sure you know whom you're getting involved with. There are a million and one horror stories about shady agents who never return phone calls, charge exorbitant "reading fees," or ask you to sign contracts with the word "soul" written in blood. Your best bet is to go through a reputable agency (eg., William Morris, the Wiley Agency), or get a recommendation from a publisher or another author. Alternately, you could pick up a book called the Guide to Literary Agents, (part of the Writer's Market series). If you choose to work with an agent, he or she will shop your manuscript to a bunch of contacts at appropriate publishing houses, help negotiate a deal, then take 15 percent of your royalties. (If you do get a contract, it's a good idea to have an attorney read it over. This is an expensive endeavor, so if you have lawyer relatives, befriend them now.)
If you get through to an editor without an agent and they want to meet with you, chances are they'll recommend an agent to you. Whoever they suggest will probably take you, considering you've already found a publisher (the toughest part of their job). If the publishing company accepts your project, the editor will set some deadlines for submitting chapters (or revisions, if you're done with the book). Some editors are very heavy handed, others pretty much leave you alone.
Once you've handed in the final manuscript, expect to wait six months to one year for the book to get out on the shelves. Chances are you will have little to no control over the cover of your book (the publisher's marketing department takes care of that).
After years of working an office job "just to pay the bills," you finally finish the novel you've been working on since graduation. Or maybe you're stirring cream into your boss' coffee and you decide you want to write a guide to finding "G.O.O.D." (Get Out of Debt) jobs. What do you do? In your daydreams, the publishers are banging down your door before you even get the last chapter out, but in reality, unless you're a celebrity or descended from one, no one's knocking.