All replies should be in . List 10 reputable guest post sites related to {{Niche Topic}}. Ensure they are of high credibility and open to guest submissions. If possible, include their contact emails. Structure this in a table format detailing the serial number, website's main themes (3 primary topics they discuss), site name, contact email (only the email, no links), and a quick tip for each. Only include the table in your reply. Do not start with any text above your table.