Consider the 3-country Selectpass if you're planning on taking in a both Germany and the Netherlands. The Selectpass gives you up to 10 days to explore 3 neighboring countries. You can choose the Netherlands, Germany and one more country to make your time in Europe unforgettable.
Look at individual country passes. Both the Netherlands and Germany offer country-specific rail passes. These passes are great for travelers who want to explore these two countries in depth.
Figure out where you want to go if you're looking at point-to-point tickets. If you plan on taking the train to multiple cities in Germany, point-to-point single tickets can add up quickly.
Take a look at the train schedule offered by Deutsch Bahn to find out when your route is running. Service from the Netherlands to Germany is frequent, making travel planning easier.
Pay for your tickets online with an American credit card. After you've paid, you can make arrangements to pickup your tickets at any Dutch railway station in the Netherlands.
Pay for supplement reservations, if applicable. Although most Netherlands-Germany routes do not require reservations, high-speed and express trains do.