Read Western literature. Visit the local library and read popular Western books. Also read literary journals that feature Western writers. There are many sub-genres under the Western umbrella. Research the many kinds of writing to get a sense of what is out there and what people enjoy. For instance, there are space Western stories online at Space Westerns and romantic Western stories at the website Love Website Romances.
Learn about places to submit your work. Visit Duotrope's Digest, which is a website dedicated to helping find literary outlets. Search for literary journals by selecting the "Western" criteria. Also visit New West, a website dedicated to providing information about the West. The New West book section lists many journals that seek Western writers. These journals and magazines usually accept short stories, though some may publish longer works. Writing for multiple literary journals also help writers find an agent for their novels. Having publication credit can help an author gain an agent or book editor's attention.
Write a Western novel. Visit Agent Query, a website that helps writers connect with literary agents. Search for agents who promote Western novels. Ask the agents about their preferences and guidelines before submitting your work. Agents can help authors find presses who want to publish their work.
Purchase the "2010 Writers Market" book by Robert Lee Brewer. This guide provides comprehensive information about agents, presses and publishers. Search in the index for "Western" publishers, and send your manuscript to the editors and agents listed in the guide. Remember to submit according to each market's specific guidelines.