Originally Posted by tile

have a look at the official webpage of the National toruist officice in Peru

I have been to machu Picchu 10 yrs ago, and plan to return next year.
apparently, trains do not start anymore from Cuzco, but from a nearby train
station that will save you a couple of hours.
and apparently there is no monopoly anymore of trains going to Machu Picchu.
Actually, the train stops neat Machu Picchu, then you have to take a shuttle
bus

In my times, tickets were all sold out. I mean, travel agencies bought all
tickets and sold only guided tours. so just try to book yr ticket online
well in advance, or be prepared to pay an overprice.