Acrobat Javascript reference and SDK documentation

I am just starting out with Acrobat and would like to find some documentation to help me.  I have searched the forum but haven't found what I need.  When I go to a link say to Acrobat SDK: Sample Guides it provides a description but I can't find any actual examples of how to write the javascript that I can put in the action field of a Button.

I'm sure I must be doing something wrong.  I am confused.