What do you mean relevant button? If it is in the ribbon, it is linked to the computer you use. It is possible to associate to a file through ui editor...but it is quite complicated. It is like creating a ribbon within the file, so the button is integrated in the invisible properties of the file
It is much simpler to use activX buttons, right click them and in the code section, paste the macro. An ActivX and its code will always be part of the file, still work if you send them by mail and open them on another computer...so I guess is what you want.