kelleyj,
I'd listen to Chunky, Birol and Jim. They're giving you some great advice.
As to what to do? Go to the bookstores in the area and look at those books that are similar to yours. Check and see what publisher published those books and write them down. Sometimes, but not always, the authors of those books thank their agents; write down those names.
Go to the publishers' websites and see if they accept unagented submissions. If they do, check their submission guidelines and follow them to the letter. (This will probably take a pretty long time, as the larger publishers have absolutely huge slushpiles.)
On to the agents. Check them out here, at Preditors & Editors, and Agent Query. See if the agent has a blog, and if the agency has a website; if they show sales of books, check them on Amazon, etc.
Write a query letter; rewrite it until it's the best you can do. (You might want to submit it to AW's Share Your Work forum so "fresh eyes" can give you an idea of what works and what doesn't.) Find the agents' submission guidelines (yes, more than one; don't send out only one, or you'll die of old age waiting for something to happen

).
Then you wait...while working on your next book or a short story or whatever.
It'll take some time to poke through...but at least you won't be out an outrageous $ amount.
Good luck.
~Nancy