Originally Posted by RazorSharpe

Do you already have a mailing application? You can look into smtp.com or sendgrid.com or even amazon's ses offering. If you also need the mailing application, I can only suggest two that I do use but there are obviously more options out there which may possibly be better:
Interspire Email Marketer
Oempro (by Octeth)

There are obviously other solutions like a SaaS offering but whatever you do, make sure you read up on reputation management and what it takes to be a responsible mailer.