... can't get it to work.
Sorry, the parallel port is pretty much a dead end these days.
You won't find it on most computers and Windows doesn't support directly playing with it.
Depending on what you want to do a serial port (or a serial port over USB) is much easier.
If you only want to turn off/on one or two things you could use the serial port DTR and RTS.
On the other hand, since these are used for communications purposes it's a bit insecure to use something that Windows itself toggles.
I ran a bread baker on that once.
If you really need multiple control lines may I suggest a Cypress FX2LP module?
Ok, that needs firmware downloaded.
You can do the same sort of thing with most small USB microcontrollers.
In the final analysis, the question is: what do you actually want to do?