SEO Optimized Wordpress Spanish Site

Basically I need someone who can build a website that has the following characteristics: Pataform: Wordpress Language: Spanish Topic: Health Products, Food Supplements, Vitamins, Weight Loss Products The project needs to be completed in about 3 to 4 weeks and what I want is a website that can drive traffic mainly from Google, Yahoo and Bing. To accomplish this I can give you examples of 2 or 3 sites that have top positions in the search engines. Yo have to have knowledge on SEO and be aware of the latest updates from Google Penguin in order to avoid penalyzing. I already have a domain with some products that can serve as the project. It is obvious that if you know Spanish you would be a more ideal candidate since you may probably have to compose some articles. I am looking forward to hear proposals.