I have four finds in Amsterdam and I don't speak Dutch. Do SECRET DOOR for sure, GC2TJKV, (I think it's big enough for a geocoin) and also Spooren Van Vroger GCINVVM by the train station like another said; intense crowds and great satisfaction for finding and replacing without being seen! I also found Amsterdam Trad's Chinatown GC2YKHW and Het Waalse Pleintje GC2NXQ3. GREAT FUN, and ENJOY Amsterdam! (I'm going back next week myself, and have a reserved ticket for the Anne Frank museum. Looking forward to it.)
Cheers,
Machtuck