The two main email marketing systems on the web are Aweber and Mail Chimp. If you are looking for something free to start off with, go with Mail Chimp. If money isn’t an issue go with Aweber – simple as that. Both of these sites will allow you to easily create sign up forms that you can add to your site. They will also allow you to create a sequence of autoresponders. This is effectively a lot of different emails that you set up, to be periodically sent out to anyone who signs up. You can write them in a way that allows your customer to feel like you are regularly sending them fresh and personal content. The great thing about building a list is that you can resell to them over and over again. In saying this once again remember that content is king. Over deliver on great information and they will be happy to spend some money on your products.