I have been told you can 'track' a bus online but I am struggling to find out how. If it is of any help the service I am trying to 'track' is the 378 from Stockport to Wilmslow.
Some companies are experimenting with it on a few routes - but it isn't really operational yet
Not sure if the signs you see at some bus stops are actually tracking the bus or just telling you the timetable. That system is widespread but I don't think the info is put on line.