Design and creation of a newsletter template

We are sending daily newsletters to our customers and we need to improve our current newsletter look and feel. We need to make sure that the layout looks good in ALL mail clients. We will provide you some ideas on what we are looking for, but you will need to create both design and code the html. The newsletter should be easily updated as we update it everyday. Only some variables will be changed, so if you can provide an interface where we can insert the variables and create the html automatically, it would be a plus. Bid with confidence, and provide some references/ samples.