Tenue de Nimes indeed. Probably the best place in Amsterdam to get some kick-ass denim. Also there is a Red Wing store, the guys at TdN can tell you more about it.
Also look for MOOS, it's a one-man made-to-measure tailoring shop. He can make you a pair of jeans, or any other basics-related stuff. Also, in the Nine Streets (Negen Straatjes), you can find the store of Jason Denham (for more info see his site:
http://www.denhamthejeanmaker.com). This dude was one of the guys behind Blue Blood, a dutch brand who makes jeans and other clothing. Some interesting stuff, as this guy really lives for his work.