Signing up to a newsletter service
We've been using that newsletter form for a long time now but haven't yet mentioned how we are going to send out the newsletters. One way to do this is to use a hosted newsletter service. There are many of these available each with slightly different offerings. Some familiar names include Aweber, MailChimp, Constant Contact, iContact, and half a dozen or so others.

Each of these services will have an API that can be accessed to update records. Some of these can be very rich and complex, others almost non-existent. However, all of them have suggestions for a form that you can include on your website for newsletter signups. This form code will give us enough to sign up our user automatically to the service.
We will work with iContact here but the same principals will apply to any of the other services.
Getting ready
We first need to find the "sign-up" form code for our newsletter service provider. iContact has a little wizard that generates a form in two versions...