Ecomerce set up and design

I am looking for a person to develop a new eCommerce website and a stand alone brand/company promotion website for LED lamps and fittings. Must have excellent artistic/graphic skills and be visually perceptive. I have the visual concept for one of the sites and would like to now progress. Administration for the site must be straight forward so that with a little training i would be able to change alter add products, descriptions etc. The right person will be required to expand on what we already have and be able to demonstrate their creativity by way of portfolio. I would prefer the successful bidder to be London based for briefings though not paramount.
I am flexible with the payment terms either hourly or fixed rate.