In e-mail marketing you have a highly targeted group of people willing to receive information from you. The response rates are therefore very high in e-mail or permission marketing as it's often called.
It's important however that you use your list of subscribers wisely by sending them valuable information and not spam. Your credibility dwindles rapidly if you are accused for spam. Many merchants might cancel your affiliate and your loyal folllowers won't be so loyal any longer if you spam.
When you get a few hundred subscribers it's not practical any longer to maintain the subscription list by yourself. I recommend you use a professional autoresponder service that automatically handles new subscriptions and un-subscriptions.
Start by reading this article about Do's and don'ts when writing a newsletter.
I personnally use and recommend the following products for E-mail Marketing.
The ultimate time and hassle saver ever built. Imagine to maintain subscriptions and un-subscriptions for thousands of subscribers by yourself. You end up working like crazy and still and up with a messy subscriber list. Not so with AWeber, they take care of all this for a small monthly or yearly fee. They have lot's of templates and other supporting material that helps you hit the ground running.
Save time and problem with Aweber
Turn words into traffic
This is my favorite ebook on how to write and publish articles. It really helps you throughout the whole process from identifying topics to publish the articles. Most of the writing techniques in this book apply for e-mail marketing as well.
Turn words into traffic is available for instant download
Make your content PREsell
This ebook is not strictly about writing newsletters but writing content for your affiliate web site. The technique to PREsell is however as valid for newsletters as for web content. You should leave the hard selling to the merchants landing page and PREsell the product in the newsletter yourself. The layout of the book is slightly messy in my opinion but i love reading it over-and-over again. It's a book that really makes you think and it's incredibly cheap.
Make your content PREsell is available for immediate download