This is one of super obnoxious chicken and the egg type questions. In an effort to get a book published, authors often run into the wall of platform and previous works.
Agents and publishers want to know that you have an audience. That people like your work. That you actually already know how to write. You know, the stuff you put in that all important Bio part of the query letter.
In other words to get published, you have to already be published.
There's always the slush pile. You can get picked out of inbox sitting on an editor or agents desk. It happened to me. This is one of those lightning striking kind of things though. Right place, right time, bottle ready to catch that lightning.
But there is another way grasshoppers. Build up your credentials. Enter Contests, start a super popular blog (I clearly do not have the machanics down on this one yet), submit short stories and essays to magazines, find places on the web looking for content writers.
Today I'm going to plug the first option: Contests. One in particular.
Mormon Mommy Writers blog is having a contest. We are looking for personal essays, short stories, poems, haiku, limmericks (just kidding), but you get the idea. The subject pertains to the title of our blog. Mormons, Mommies, and Writers. Write about one or all. You don't even have to be a Mormon or a Mommy to enter. Just a writer. Winners and honorable mentions will be published in an anthology.
So enter hopeful writers. What do you have to lose. Nothing. What do you have to gain. A publication credit. Something to put on that bio section.
Good luck! For more contest info use the above link. Submissions must be received by July 31. And yes, I am one of the judges.