If you're new to the horror genre, you might be interested in the Mentor Program offered by the Horror Writers Association. Under this program, HWA matches up new and aspiring writers with experienced and knowledgeable members who are already widely published. The program not only supports the writing process, but also provides advice on how to prepare query letters and submissions.
To join the Mentor Program, you have to be a
paid-up member of the HWA. You can then contact the Chairperson and provide details of your membership status, information on your writing/publications, and an explanation of what you are looking for in a mentor. Because of the popularity of the program, you may be placed on a waiting list until a mentor can be identified for you.
For further information, please visit the HWA website at http://horrorwritersassociation.info/ and choose Our Mentoring Program under "for writers" in the right-hand menu.