Can i apply for a visa at the Shenzhen Airport upon arrival or somewhere in Shenzhen while there?

I was verbally invited to be a vendor at the International Licensing Fair in Shenzhen, August 15, 16, and 17. I have hotel reservations in Shenzhen, am coming alone, and will not be leaving Shenzhin until i fly back to the US. What kind of visa do i need and how much does it cost? Please and thank you. My email address is. les10lieaol.com

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