Where is the best place to download domestic wordpress themes?

A lot of foreign sites can not be opened, I can understand part of the English slag, but download down the resources and a lot of foreign plug-ins, really make me a pain in the ass, can not find a good solution.
I have the following needs and am begging for someone's help
1. wordpress Chinese theme website, the best can preview
2. recommend some good plug-ins, and common plug-in usage
3.DEMO data how to import templates