If you use Feedburner to email newsletters to your blog readers, you can get the list of emails of your subscribers when you sign in to your Feedburner account. Feedburner even offers csv email list download thereby making it possible for you to carry out email marketing using your csv email list.
To download the email list of your Feedburner email subscribers, follow me through the steps below:
==> Sign in to FeedBurner.com
==> Click on the name of your feed.
==> Click the "Analyze" tab.
==> Click on "Subscribers" under "Feed Stats"
==> Click on "FeedBurner Email Subscriptions"
==> Click on "Manage Your Email Subscriber List"
==> Click on the "CSV" link beside "Export"
You will be prompted to save the csv file.