Tourist visa applications (Beijing)

Hi
i have a work visa and established residency teach esl in Tianjin, I want to apply for tourist visas for travel in January when I have 5 weeks off. i wish to go Japan Taiwan, Hiong Kong Thailand and Singapore.

Can I apply at any US embassy in Tianjin or Beijing?

Do I need to fill put an application for each country? can I do it on the internet or mail them in?

Any explanation on the process is welcomed.