As a Brit, I also agree with the comments re getting your visas (both of them) before you leave the States. I would also agree with doing China first and then Oz last. If you are cunning when buying your ticket, you may even possibly get a stopover in Honolulu or one of the W coast cities on the way back for free. Have a long chat with a travel agent in New York. I quite like www.statravel.com, but there are tons.
Anyway, good news. The PRC has a consulate in New York; it's visa information is available here.
10
________________
Pro tip
Lonely Planet
trusted partner
trusted partner