I apologize if this question sounds stupid to alot of you.... But what would be the best way of mass emailing my past customers for promoting related products? I have about 70,000 customers who have bought my iPhone product, so that means that they own iPhones and would be interested in many things. However, I never had them added to an emailing service(aweber, getaresponse). I know I can upload the emails to one of those services, but that requires each of them to confirm their email subscription before being added to the list. I don't want to have to do that because I know it will be a disappointing signup rate because alot of customers bought the product up to 4 years ago and might forget the website name. So my question would be, is there anyway of me emailing these customers with a service/software for the purpose of weekly emails/promos where they can unsubscribe from each email blast, but don't need to "signup" to begin with????