FBM Merchant Fulfillment: A method of selling on Amazon in which a seller lists their products on Amazon, but handles all storage, shipping, and customer support themselves or through another. 1. Write your name and contact details. Write your job title, full name, and company name in the upper left corner of your letter. Your business address, phone number, and email address are usually found below. All details should align with the left margin of the letter and have no indentations. 2. Include the date.