You can definitely use command line parameters in Notezilla .
You can create shortcut files on your Windows Desktop, Windows start menu or in the Quick Launch toolbar to execute the following actions.
Note that when creating shortcut files, you must specify the complete address of Notezilla .exe. Example: C:\Program Files(x86)\Conceptworld\Notezilla\Notezilla.exe /CreateNewNote
To know more about the different command lines an their subsequent action, visit this page:
http://www.conceptworld.com/Notezilla/Help#Command-Line-Parameters
There is no API as such.