Australian in USA for an extended period, I'm wanting to visit China now

Thank you Lawrence for your answer however I don't think I was clear enough :( let me clarify it please :)

I am an Australian visiting the USA for a few months visiting friends and family. However a friend and myself want to go visit China for a month and then I come back to finish off my visit with family here in the USA. My friend is American so she lives here, I have a visa that allows me to come and enter the USA multiple times. So my question is " can I go to the PRC in Los Angeles? As it's the closest to me and what forms do I need to fill out and what do I need to submit please so I can qualify for an entry permit to visit PRC please ? :)

Thank you very very much
Karen Mendoza