To launch a successful e-mail marketing campaign you must reach the right targeted audience for your business. In order to do that you may have to do one of two things: Have a great customer tracking system in place or buy a targeted mailing list.
If you have a customer tracking system in place, you have the whole system licked. You have your customers’ needs at your fingertips and can target your e-mails and direct mailings towards those needs. Should that not be available to you then you might want to go with option no. 2.