I understand that most of you talks about professional handlers.
Do you think I can find smwhere infos about handling. I would like to learn basics of boxer-handling...
Off the top of my head, a couple of good resources (non-Boxer-specific) are the books "The Winning Edge" by George Alston, "Click to Win" by Karen Pryor, and the videos by Michael Kemp. Rick Tomita's "The World of the Boxer" has a nice pictorial section on properly stacking your Boxer.
As far as Boxer-specific handling, the best thing to do is apprentice under a Boxer handler (this would include a successful owner-handler).