The Hemp shops, http://www.hempshopper.nl will rent you a vaporizor while you are in Amsterdam. This will allow you to vape, not only in the coffeeshops which have vaporizors, but this way you can vape back in your hotel room. Most coffeeshops in fact do not offer vaporizors. A small list of those who do include Katsu, 420, Amnesia, to name a very select few.
There are 2 locations: Nieuwezijds Voorburgwal 80, Amsterdam, The Netherlands - Phone: +31 (0)20 528 55 56
Hempshopper, Singel 10, Amsterdam, The Netherlands - Phone: +31 (0)20 773 70 14
http://www.mediwiet.nl/ (in Dutch)
http://www.kweekotheek.nl/ (Dutch grow lights)
http://www.sjamaan.com/, 31-026-389-3819
http://www.amsterdamheadshop.com/
http://www.dampkring.nl/h/head-shop-amsterdam-dampkring.html
www.elephantos.com/en/head-shop