Can a GPS navigation device be tracked?

Does anyone know if there's a way to track the location of a GPS device knowing its ID? Are there any websites where this information is available?

No, GPS location determination is a problem of precise time measurement (from the beginning of a special week), and sattelite identification. To not go into any details ... it is a one way signal from satelites towards earth, and can not be tracked.

http://en.wikipedia.org/wiki/Global_Positioning_System
http://en.wikipedia.org/wiki/Radio_clock#GPS_clocks

Differentical GPS's are a different matter.

Tracking via GPS navigation (this is a requirement which for example trucking companies have which enables them to locate their vehicles) is a "simple" mechanism of sending out GPS information (NMEA) via an automated SMS messaging service to a centralized location. Very simply put of course, but that is the basic principle.

http://en.wikipedia.org/wiki/GPS_tracking
http://www.uktelematicsonline.co.uk/

Time: Why You Can't Track Your Stolen GPS Device

It's a cruel irony: Car navigation devices keep you from getting lost, but their location-sensing acumen won't help you find them if they get lost or stolen. Why not? Because location and tracking are two different matters. "The GPS calculates location for you. Communicating that location to a tracking center requires a separate service," says Kanwar Chadha, founder and vice president of SiRF Technology, the largest supplier of GPS chips to navigation device makers.

further...

Personal navigation units could easily incorporate the same features, but device makers say there's little demand. "Most consumers are just looking to get from Point A to Point B," notes Tom Murray, vice president of TomTom.