Here are various videos showing nicely the forehand and backhand technique
Chinese champion Ma Long discusses his forehand drive technique followed by commentary of a Chinese coach. This is a very long video demonstrating many techniques broken down into chapters. Just view this part several times to get his main points.
Another forehand drive tutorial by coach Yang Yang which gives a more precise points.
Coach EmRatThich pointers for developing good forehand drive.
Forehand drive stroke taken apart into its most basic elements by English & Irish champion Jason S. – here
Forehand shown by an Australian Pro William Henzel in very slow motion with comments and common mistakes pointed out. Very instructional. Forehand counter hit & block. However, his technique relies on accelerating by whipping the wrist more than body rotation. He also advises against opening the racket (more force) too much and for closing the racket (friction).
Video of various forehand techniques taught at the Chinese table tennis school made by a group of visiting French junior players. One thing to note is the relax-squeeze technique used to speed up shots and recovery to ready position shown starting here.
Another backhand drive stroke video – here.
Article about active backhand blocking and its advantage over passive blocking.
Backhand block shown by Ping Skills’ Alois Rosario
Backhand block shown by Russian coach
Active backhand block shown by Canadian player Jean-Luc Hinse