Best banks to use when traveling in Netherlands?

Withdraw money from ATMs, using your debet card - do inform your US (?) bank in advance that you're planning to use your card overseas so your bank won't block it for security reasons while you're on the road. Forget about bringing large amount of cash or travellers cheques.

Local ATMs don't charge a fee, it's your own bank that does. Make sure you're aware of their exchange rate and charges for overseas withdrawals beforehand, to avoid unpleasant surprises after you get back home.

As Aribo mentioned, your best, safest and cheapest option is to use your ATM card. Banks do not always have the cash on hand and hotels tend to give you a horrific exchange rate. You also have the GWK exchange offices, which are alright and perhaps one of the better options should you have a lot of cash that you need to exchange. They also accept the biggest variety of currencies and their rates are reasonable.