my store

My case was P sold products to D company and I paid for D as lending money to D.
when I asked D to return my money and D said not received the orders and P refused provide any document for me. P is in IN US, D is in Shanghai. My sister who borrowed money from me has passed away unexpectly. her company D even didn't write any paper for me. one of P and D was lie. I only have bank of statements to prove I wired money.

I am in CA and who should I ask for help? how to file lawsuit to federal court?

Thanks,