My Novel is Finished

I've been working on writing a novel for the past year and a half. I finished writing the story a few months ago and I've spent the last couple months re-reading it, fixing inconsistencies and re-writing awkwardly written parts. The name of the novel will be "Little Boy Lost". It's about an up-and-coming young executive and his wife who are traveling cross-country due to his transfer from the east coast to the west coast. They are driving in two cars, taking turns with their two year old son. At a rest stop two hours from their new home, they inadvertently leave their son, each parent thinking the other one has him. A young, poor local woman finds him and decides to keep him. Now that I have it done, I have to decide what to do with it. The advice I've been given is to find an agent. Naturally, I have no idea how to do that. Someone told me to go to Barnes and Noble and get a book called, "Writer's Market" which will give me all kinds of information about how to get a book published as well as the names and addresses of agents. When I looked online I found a website named "Writer's Market" and it seems to be the same thing. You have to pay to join, but it seems like it will be worth it since it's interactive and updated daily. Does anyone know anything about publishing a book? Anyone have any experience? I'd love to get into a dialogue with anyone who can help me.