Todd Carnes submitted a new resource: FocusWriter - FocusWriter is a simple, distraction-free writing environment. Read more about this resource...
On my Mac version, the typewriter sounds need to be turned on in the preferences, in the first "General" pane.
According to the "Release Notes", they should be there for a long time by now. I also see screenshots of the Windows version with the typewriter sound option. Maybe you just have a really old version?