For group Beijing tour, 4days, conducted by a Travel Co. Do I need any documents to get the Visa?

During my visit to Seoul, Korea from Oct.1- Nov. 5, 2014, I am going to take a '4 days Beijing trip' with a travel group by 'Hana Tourist Co'. The Beijing trip dates will be from Oct. 6- 9.

I already made a reservation for it at Hana Tourist Co. The Hotel name in Beijing in which we will stay is 'Double Tree by Hilton Beijing'. I now have round e-Ticket from L.A. to Seoul, Korea of Korean Airline. However, I don't have the air ticket from Seoul to Beijing. Air ticket will be handed to the members of tour group at the airport on the departure date. I have a copy of the Tour reservation paper by e-mail which is Korean character. I don' have any invitation document from China, because it is the regular group trip conducted by the Tour Co.'

In this case, can I apply and apply here in L.A. ? Do I need any other document to get it?