I had been looking at Online Newsletter generating services, and, I was surprised to find that they are pretty expensive (around 10$ per month). I spent a day to create the newsletters and sent it through Entourage. Most E-Mail clients cannot send complex HTML E-Mails and usually require some kind of an add-on script. For Entourage I used this, an excellent Script that worked very well.
My newsletter looks great in Entourage,Gmail, YahooMail and Hotmail. Hopefully I will be able to send more of these in the future.