I've been recommending MailChimp for years. Probably as far back as 2009. Part of that is because they have a free plan which is great for small businesses. The other part is that they have a phenomenal user experience. Everything in their system is easy to use. That's why when I started marketing my book I signed up for a MailChimp account. As of today I've been using it a full year and I've learned quite a lot in that time. I hope you can learn from some of my mistakes.