Design 3 electronic website banners/ads

I need to get 3 different size banners and ads to give to my affiliates to help promote my website. I am looking for more than a graphic artist, I am looking for somebody to help me create ads that pop and have some kind of marketing strategy.

I am selling health foods, so it is a bit of a niche market. In particular raw vegan, gluten free foods. So I want to create something that incorporates my logo but also portrays the image of health and well-being. Something that will draw people in.

I want a few sizes so that my affiliates can integrate them into different sections of their website. i.e. a longer thin banner, a square banner and a skinny long one.

my website is: www.trulyorganicfoods.com to give you an idea of what my business is all about.