Great, I suggest you drop Michael a line, I'm sure he has some suggestions on litterature in english.
On heraldry you can start here: http://www.danbbs.dk/~stst/slaegt_adelsvaaben/0_adelsvaaben.htm
This is a fantastic resource for gamers, thanks very much for sharing. I'm looking for ideas for Northern Crusades, and this has loads of great heraldry from the 12th and 13th centuries.