Build a Website on top of Wordpress with social features

We have a PSD of the website design (headers and footers, etc..) we want a website built on top of Wordpress that will use the wordpress login & registration system to log the user into the "website", and then they'll be able to add friends (other wordpress users), as well as send private messages to them. This wordpress site or template will use the styles and graphics in the PSD file. Users will be set up with Wordpress's existing database system. Optional feature (quote separately please): * Setting up user groups (groups of friends can set up groups with a name and image where they can share messages among the group members only). * "Account" page that will show the user's personal information, along with amount of credits (credits will be an entry added in the user's table in the database, default is 100 credits for all users).