It all depends on what is your email marketing goals. Do you just want to send emails or do you want to conduct more advanced behavioral targeting emails? For simple emails, check out: Constant Contact, Survey Monkey (yes they do emails), Emma
For advanced: Bronto, Gold Lasso
For sure, Email marketing is one of the best way to increase your traffic. But it should be mentioned that Emarketing doesnt suite everyone. I mean that not every website needs in such service. For example if you have a blog it is not really necessary to do Emarketing. But if you sell some goods and you have new arrivals all the time, so obviously it would be much better to start such campaign.
Yes Email marketing is the best way to spread your message locally and globally. if your question is that how we can take advantages then it depends on your goal of email marketing... if you are selling online products or services then E-mail marketing can help you to generate leads for your business!