Pick up a copy of the most recent "Novel & Short Story Writer's Market." This book collects thousands of book and magazine publishers for fiction, and tells you where and how to submit your stories for each publication. "Novel & Short Story Writer's Market" also details the genre and kinds of stories for most, if not all, publications. This is probably the most important thing to know when trying to find a publisher. If your story simply isn't within the genre or scope of the publication you submit it to, it'll never get published regardless of how good the story may be.
Search social networking sites such as Facebook, Twitter and LinkedIn for publishers and those employed by publishers. This can be an interesting way to meet editors for a publication. You probably won't get any special treatment going this route, but you should be able to get some answers about submitting to a particular publisher. This is a smart route to take for someone who prefers to talk to people instead of searching through listings in a book.
Read the copyright pages of your favorite short story collections. Most short stories are published in a magazine or journal before an author puts them into a collection. The copyright page of the collection lists where stories were published prior to the collection. You can visit the websites of any publishers that interest you, and learn how to submit your work from there.