Web designers and developers know really well about creating websites. In other hand, they know very little about your business. In general, your are going to need a logo, product and service descriptions and titles, a summary of what your business is about for the about page, contact information, product and service images, privacy policy, shipping policy, return policy, terms of service. Usually your business plan should have this inhformation. If you dont have a business plan... no worries there are hundreds of websites on the web offering similar services that you can use as a guide.