Press Ctrl+N to open a new item for whatever part of Evolution you're working in. In mail, this means you create a new message. If you're looking at your address book, Ctrl+N creates a new contact card, and in the calendar, a new appointment.
Use File > New > Mail Message or Ctrl+Shift+M.
Use File > New Appointment or Ctrl+Shift+A.
Double-click in any blank space in the contact manager to create a new address card. You can also use File > New Contact or Ctrl+Shift+C.
File > New Task or Ctrl+Shift+T.