Banner design for a t-shirt contest site web 2.0 style

I want a banner 464 x 176 pixels for my page. and a smaller one similar style 200 x 200. Its about a site with a t-shirt contest and the banner is to tell people what to do(design a t-shirt) and earn money and what is the contest about. I want something good looking proffesional,clean web 2.0 style. People who bid must have a portfolio to showcase(its better to know about fashion and illustration design)and when the winner will be chosen, must give the banner to psd or vector format (source files). If im happy with the result we can work for lot more projects in the future