MailChimp

(Up to 2000 Subscribers = Free // 2500 Subscribers = 30$)

Your Mailing List Provider

(Up to 1000 Subscribers = Free // 2500 Subscribers = 10$)

AWeber

(Up to 500 Subscribers = 19$ // 2500 Subscribers = 29$)

iContact

(Up to 100 Subscribers = Free // 2500 Subscribers = 29$)

Campaign Monitor

(Up to 500 Subscribers = 15$ // 2500 Subscribers = 30$)
(Alternatively you can also use their “Pay per campaign” plan: 5$ per campaign + 0.01$ per recipient)

Further Reading

• E-Mail Marketing (Wikipedia)
• MailChimps Free E-Mail Marketing Guides (MailChimp)
• Bulletproof Email Marketing: Overview, Tips and Tools (InstantShift)
• Design And Build Email Newsletters (Smashing Magazinee)