Once you have the web server set up and running, you need to make sure your Drupal site can send emails, like registration confirmation, password change etc.
For inbound email, you may want to use email services like that offered by Google Apps. They offer good spam protection and secure storage.
To send email from a Drupal-powered site, you can use an SMTP module and do it all through a third party mail service. Alternatively, you can set up your own SMTP server. This article describes setting up an Exim server that allows sending emails.