Wasserzeichen:
http://www.ksbm.oeaw.ac.at/wz/wzma.php
Die Hausbucher der Nurnberger Zwolfbruederstiftung
Swiss mss., or in German
Global Catalogue of Digitized Manuscripts
Oxford Catalogue of Incunabula (Bodleian)
Illustrated Blockbooks (up to 1500) in the StaBib. Munich
French medieval mss. (esp. for animal lore)