Can you travel by train from amsterdam to berlin?

Can you please give the website. Thnx

You can, but there are two websites to find out the current price. One is
http://www.ns.nl
and the other one is
http://www.bahn.de

They both won't give you a price information that's really reliable. The one thing I do quite often is take a ticket on a "last minute" basis from KLM (Royal Dutch Airlines) or Lufthansa, which usually costs less, and the flight lasts 50 minutes, instead of the eight hours (!) you'd spend on a train.

Yes, it is possible. Try this website - there are probably others
http://www.eurorailways.com/

u sure can.

Yes.

http://www.ns.nl and http://www.bahn.de

Normal travel time by train is roughly 8 hrs and normal fare is around 120 EUR one-way.

The cheapest method is by the special offer train ticket Schoene-Wochenende-Ticket (=SWE) and costs a bit over 33 EUR one-way. Essentially you take any train to the German border very early in the morning of a Saturday or Sunday and then use regional trains to get from the German border to Berlin.
You need to work out a schedule beforehand using bahn.de. Select "only regional trains" or "without EC/IC/ICE" to find workable train connections from the German border. Travel time is roughly 14 hrs with this method. The advantage is that up to 5 people can travel on SWE together for the same 33 EUR, so the price cannot be beaten when you are in a group. You'll also often find people in train stations looking for partners to share a SWE ticket with for a small fee, so you can save money this way too.

Alternatively there are bus and plane.

http://www.eurolines.com
http://www.skyscanner.net

yes, I do that twice a month.
the international train leaves Amsterdam airport Schiphol 1 time per day (10:48) and from central station 4 times a day (7:04,10:57,14:57 and 16:57) its 6:08 minutes journey in a comfortable train with a bistro but no smoking.

have a nice trip
costs: one way ticket is 70 € but if you book more than 3 days in advance you safe up to 40%.