Another way to find a literary agent is to go to your bookshelf, pick up a book, and flip to the Acknowledgements page. Read over the page carefully. You are searching for a name of a literary agent. You can than take that name and Google:
(The name of the literary agent you have found) literary agent.
A bunch of pages should pull up, so all you have to do is click on a page and see if it says what literary agency it's from.