Landing page design

I am looking for a landing page psd to be created for a social website that will focus on conversion, be neat and professional. The design must be for web as well as mobile/tablet devices. Accordingly, I will need two or more versions of the design. I will provide the website url to the shortlisted designers.

I will look to redesign the entire site with the chosen designer once this job is completed and how well it is done.

Thanks