Most people who try to publish their work using traditional methods will look for a literary agent a few times in their writing career. Finding a good agent is a heavy task that takes time and perseverance. There are a few places where you can look for agents, but here is a nice infographic published by WritersMarket.com. It gives you a visual idea of where is the biggest concentration of agents. Of course, you will still have to write a killer query letter, but finding some agents to send it to is also important.
Did you go through an agent search process? How was it?
All the best,
Iulian