I actually just published a book 2 weeks ago! It's titled Homecoming, and you can check it out on Amazon if you want!
I am just starting out and really no one knows me, is that marketing is TOUGH. You have to start from scratch, reach out to people, and it is a slow, slow process.
But don't lose heart! All new authors (especially me!) have to start there!
I have built a blog (check it out in my signature), created a Facebook fan page, a Twitter account, a GoodReads page, a LinkedIn profile, and a Pinterest. These aren't the only things, but these are the best social media platforms to work with.
But the most important thing is to MEET PEOPLE. Reach out on forums like this, be involved in discussions. You will find your readers in places where your genre is devoured and loved, and they will be enthusiastic to help you out if you mean business!
And check out doing some blog tours or hiring a publicist. Even though it will cost you some money, the help that these can provide you is more valuable.
I hope this helps! If you have any other further questions, feel free to message me!