Austria:  http://www.post.at/eshop/philatelieshop/category.php?maincatid=1 

Bosnia & Hercegovina (Croatian Post Mostar) http://www.post.ba/about_stamps.php
Bosnia & Hercegovina (Federal post Sarajevo) http://www.posta.ba/stranica/2/25/23.html#Postage_stamps
Bosnia & Hercegovina (Serbian Post Banja Luka) http://www.postesrpske.com/sites/media/Filatelija/KatalogSr.pdf

Canada:  http://www.stampedia.net/stamp/catalogue/PA,CAN/BRIEFMARKEN/KANADA/de 

Croatia: http://www.posta.hr/main.aspx?id=84

Irleand:  http://www.emerald-isle-gifts.com/irish-stamps---philately/commemoratives-2000-07.asp 

Macedonia: http://posta.mk/english/filatelija.aspx

Slovakia:  http://www.pofis.sk/en/catalog/products

Slovenia: http://www.posta.si/stamps/1106

UK:  http://www.royalmail.com/

Worldwide:  http://www.wnsstamps.ch/en/ 
http://www.postbeeld.com/en/fsc/home/