Need a Designer For Social Website

We are a small start-up looking for a temporary web designer to either enhance our existing web site design or develop a new web site design based on the specific information that needs to be conveyed to the end users. The web site is social in nature; we will share more details regarding the project after bidding is complete. We are looking for a designer who has the vision and ability to create a design that is both functional, yet visually appealing. No coding will be necessary; we simply seek someone who has the ability to create the design mockup.