Most newsletters are designed this way. You can charge for your newsletter, but this is usually done once you have established a strong customer base and have been in the industry for awhile. You need to establish yourself as an expert before you begin charging. Newsletters are a great way to get more exposure writing for other publications. People who see your newsletter may read it and ask you to write a short piece for the local paper, or speak at some small business organization.
Newsletters get more respect than flyers and other direct mail pieces.
Newsletters are saved and referred to like magazines. Ask some of your customers to write a short piece about their business for your newsletter. Try to get guest writers on a regular basis. Use software that will allow you to create a newsletter template. This way you can use the same format from month to month.