What is the best and or cheapest way to get from Brugge to Amsterdam by train? Buy in advance through raileurope (around $70 it seems) or is there a better way, such as brugge to antwerp then to amsterdam etc.
Never purchase tickets from RailEurope...they are a rip off. Use this site instead: http://www.nshispeed.nl/en The high-speed Thalys trains via Brussels require advance reservations, the earlier you book the cheaper it will be. The regular IC trains via Antwerp require no advance reservations, simply purchase your tickets at the station on the day of your journey. Fare is about 40 euros.
When I went to that website it seemed to be 47 euros which is about $64, when the raileruope was $67-70. What about not reserving and going to antwerp and then antewerp to amsterdam?
Not reserving and sticking to the IC trains via Antwerp is your best all-around option. It gives you more flexibility. If your journey is on a weekend, be sure to verify the schedules. The tracks between Bruges and Antwerp have a habit of being closed Sat/Sun for track work. If so you will have to travel via Brussels.