To be certain, I recommend:
* Consulting your owner's manual: This will have a diagram showing the location of the PCV valve.
* Using a repair manual specific to your year and engine: This provides detailed diagrams and instructions.
* Searching online for "2001 Ford Ranger [Your Engine Size] PCV valve location": You'll likely find images and forums discussing its location.
Don't hesitate to take pictures of the engine bay and post them online (to a car forum, for instance) if you're having trouble locating it. Someone familiar with Ranger engines can help pinpoint it from an image.