We encourage all authors to consider their options. Here are a few resources that are well known, but "just in case" you are not aware of them.
The old bible of getting published is still worthy: Writer's Market.
We are too new and perhaps too hybrid, to be listed in the current hard copy edition. There is a big emphasis on agents in Writer's Market. We recommend double checking any information there with a search of the market, or agent's, website as Writer's Market does age and there have been some complaints that the website is harder to use than the book. (Trial available, but not free)
There are some specialty lists of markets. One is Market List which has some broken links and looks like it may be a work in progress, but we don't hold that against them as we are new ourselves. This currently focuses on Science Fiction, Fantasy, and Horror. (FREE).
A fairly good online list is Duotrope. This has poetry also and an interactive search on the landing page. (FREE)
Wooden Horse Publishing offers some guidance, learning materials, etc. for freelance writers. While not specifically geared toward authors of full, novel length, manuscripts, it is an interesting resource that has been around for some time.
If you really are set on finding an agent, you should look at AgentQuery.com.
There are a number of reasons that a writer gets rejected by a publisher (or agent). This recent blog entry on writer's digest summarizes one of the reasons we often reject manuscripts. Persistence Doesn't Matter If You Make This Common Mistake
There are a number of books, versus websites mentioned here, that cover these and other writing topics. We recommend searching retailers for those books and do not endorse any individual one.
We will update this from time to time with useful links pertaining to publishing, authors, and related subject (e.g. eBooks).
We encourage you to submit, but in today's digital world there are many who simply want to publish on their own, or certainly research it. One group that follows our ideals of community is the Independent Authors Guild. Take a look at their website and consider joining their discussion group.