This page is just for reference.
Optional: To set up a personal account (with Otis email) which will enable you to save materials and searches, click here.
Materia - database with manufacturers contact info.
Materio - costs a lot to join, but the pictures are nice.
Core77 - There's an RSS Feed on this blog that could be good for this page...
http://ecolect.net/ - sustainable
http://www.mindsetsonline.co.uk/index.php - has materials you can order, like inventables. REALLY fun stuff.
http://www.matrec.it/en/ - requires subscription, education discount.
CCA Material Library - nice database, open
MaterialProject.org - a material and building reference
Style Park - database of materials with manufacturer info.
Transmaterial - blog.
http://ecolect.net/blog/ - blog
http://www.architerials.com/ - blog about new materials
http://extranet.kingston.ac.uk/rematerialise/search-materials/search.asp - nice searchable. must register, though.
http://inhabitat.com/products-2/ - a nice blog with new products