What are some of the useful board games used in soft-skills training and where can we get them?

Perhaps the best one, though may be a bit dated is "Acquire" a game relating to building property and taking over via acquisition and mergers. Tough to find though. Love to play with kids, adults, friends. Great team building tool.

It depends on which training you're having ,and the training games are varient such as "the oposit letters and numbers", " pop the baloons", "sticky colored notes", " throwing the ball and say what you've learned until now",...etc

I don't know . I leave the answer for professional. 

balloon training 

building tower from available material but this tools come from Germany