Where Do Agents Fit In
Some publishers won’t talk to you without an agent. Agents have contacts with various publishing circles and pitch your manuscript to publishers on your behalf. The better deal they get for you, typically the more money they make, so they are motivated to get you as much as they can. They also do the work of negotiating a contract for you. New writers will at times jump at the first offer because they are excited to get noticed. Agents help keep it real for you.
So how do you find one? Chuck Sambuchino has many resources that are great for a young writer. He introduces new agents that are looking for writers to represent. You still need to do your research and be realistic. The well-known agents are looking for well-known authors, or at least ones they feel will make them lots of money. New agents that are willing to take a chance on you are worth more than the agents that won’t even look in your direction. Just think, maybe you can come to fame together!
Agents have certain genre they specialize in, like publishing houses, because that’s where their connections are. Pick one that fits your style. And make sure you click with your agent. It will be a close relationship so you have to be ready for the long-haul.
Keep in mind that every layer you add between you and your published book will be that much less money you get to pocket. Most writers aren’t in the business to get rich (although that would be an excellent bonus!). With the expansion of indie presses, the need for an agent is not as great as it once was. Many independent publishers will consider you even without an agent. But make sure you have someone knowledgeable read the fine print on the contract before you sign it.
Mystery Writers of America has a good article by Scott Adlerberg about agents on their site http://www.mwany.org/2016/04/how-hard-should-you-try-to-get-an-agent/ .