Need a commercial website built, but where do I start??

This site will have board games and will be a pay site.  For instance if i wanted to have the game checkers built into the site and wanted to have a place where people could chat to one another, would i just hire someone to create the board and the chat room from scratch?  What language would something like this best be programmed in and why?  Any idea of the degree of difficulty involved in having contactors build such a site?  And finally, in terms of people being able to use their credit card to pay, how would i go about that?  Thank you.