Ivy this is an example of the newsletter signup we could add to the sidebar: Click the button to see the form.  I set up a “General Information” list that this button dumps into.  When a Person adds their info here it goes to the General information list.

Then when sending an email campaign in the newsletter system you would just select the “Genernal Information” list and the campaign would go to those people.  You can have multiple lists.  I also set up a  “coaches list”.