Immigration at Schiphol airport for non-EU citizens?

There are likely sites which show the average time for crossing borders, but having used the airport quite a few times I would say it depends on many factors.

If you have a short walk through the airport and are at a time there is a short queue, you could be seeing the officer 10 minutes after you left the plane. On the other hand, if you land at the same time and have a long walk, several other planes may have unloaded passengers between you and the immigration office and you may have to wait an hour.

I do not know how long the interview will be, I see many people being passed through the 'all passports' queue with just a good look at the passport, a few words and a stamp, but I also see people who are guided into a side room where they have to wait.
As a local I do use the EEA/EU passports queue, not the same you need.

From the immigration office you walk through the area where the luggage is returned to the passengers and on through customs which usually does not take any time at all, but if you have things to declare or are picked out for a random check can take minutes to half an hour.

If you want to know the timing to make reservations for a rail reservation, do not unless you have to. Only going to France or Germany it is worth it to have a reservation, all nearer destinations have good connections or direct trains that do not need a reservation.
If you want to know the timings to arrange being collected at the airport, tell them you call when you have left the secure zone, you have a good safe place to wait at all times of the day and night.
And if you want to know because you are curious, do not worry, it takes as long as it takes.