If you mean just the sign-up managed by Concrete5, you have add-ons that do that already:
For 5.6:http://www.concrete5.org/marketplace/addons/email-list-signup/...
For 5.7:http://andrewembler.com/application/files/8914/3578/2310/email_list... Orhttp://concreteconversion.com/addons/optin/features/...

If you mean managing the whole sign-up, mailing, following... There is only one add-on doing that for 5.6:http://www.concrete5.org/marketplace/addons/mailing-list/...
And none for 5.7

Having said so, I strongly recommend you use a professional mailing service such as Mailchimp, or Aweber as they have very high deliverability rates. Delivering your own emails through Concrete5 might not work as well as expected and your emails might be banned after a while.

For examples, if Gmail notices that you are sending hundreds of emails at the same time to hundreds of their users, you might be flagged as a spammer. Mailchimp and others usually don't have this problem.

If you want to go that way, for 5.7 you have this add-on:http://www.concrete5.org/marketplace/addons/form-plus1...

For 5.6: there is the same one:http://www.concrete5.org/marketplace/addons/form-plus/...
There is also my add-on:http://www.concrete5.org/marketplace/addons/ecommerce-to-mailchimp/...
But that one is specifically for ecommerce buyers. It presents your buyers with a sign-up form to your mailing list and saves all their buyer data against their Mailchimp profile so you can target them more efficiently with your marketing campaign