Company Intranet Site (Front & Back End) Development

We are seeking a coder to develop a front end (design) template and back end (admin) system for a new company intranet site. The site will be used for internal communications and should be very clean and easy to navigate and update. We have a template design idea that we would like this to look like as well as a full list of functionality we would like to have on the site. We would like to have a back-end system developed that will allow us to simply login to the admin section and be able to update copy and images and upload documents (PDF, Images, Video, etc.)...essentially a website editor on the back end that is very user friendly and allows the site content to be updated with a few clicks. We will host the intranet site internally, or through our hosting company, but the site will never be made public...as its only for internal communications. Hoping to have the full site live no later than Monday, August 13, 2012.