Online Resources:

Coach Yangyang Jia

This beautiful young lady has excellent advice for players from beginner to intermediate level.
She explains how to hold the paddle, how to stand, how to move and then covers all the strokes.
She has advice for footwork drills and even offers tips on cooking Chinese food.
Yangyang's Youtube Channel

Coach EmRatThich

Nobody knows who he is but we know he is from Viet Nam and currently living in France.
He shares many Chinese Table Tennis secrets. In addition to his excellent coaching, he also provides behind-the-scenes info such as "The Truth Behind The Forfeit of Ma Long, Fan Zhendong and Xu Xin in China Open 2017"
Coach EmRatThich's Youtube Channel

This website is possibly the easiest way to look up ratings for any table tennis player.