The following are the guidelines for submission.

• Manuscripts should be 500 to 5000 words in length. Exceptions will be made either over or under the word limit based on quality. Poetry will be considered.
• Manuscripts should be single spaced with breaks instead of indentations to denote new paragraphs. Please use size 12 Times New Roman font. Manuscripts should be submitted in DOC or DOCX formats.
• We accept electronic submissions only through the following email address: submissions@horrorworld.org. Please allow up to 3 months for a response.
• No multiple submissions. Please wait until you receive an acceptance or rejection before sending another story.
• We accept simultaneous submissions, but please let us know if your submission is accepted elsewhere.
• Payment: Horror World pays 2 cents per word for First Worldwide Electronic and Print Rights. Payment is made upon publication.
• We will be accepting submissions until July 1, 2012
• Any type of horror-related story is acceptable but we are looking for stories that are scary and original or stories that bring a fresh perspective to a familiar trope.

Source: http://www.horrorworld.org/hw/horror-world-announcements/