How do u guys get to know yoyo pros or big yoyo company bosses? How do u get in contact with them?

Some of them just hang around on forums. Most people just meet them at contests and such.

Some people get “discovered” at contests that they win or just do really well at.  if you’re lucky you could get discovered like in movies: just playing in the streets and being noticed by a superstar.
you could also like contact the companies( and talk to them(e.g give feedback on yoyos,etc)