BizTalk Training Resources

Where to start learning Biztalk?
First of all here's an interesting post that explains the way Biztalk works by Steef-Jan Wiggers.

A more detailed picture of the BizTalk architecture:

Or if you're interested in some more detailed Biztalk architecture posters:
http://www.biztalk247.com/posters.aspx

Here's another great reference, here you can find a list of tutorial video's, books, virtual labs, and more: http://sandroaspbiztalkblog.wordpress.com/2011/07/13/biztalk-training-resources-virtual-labs-tutorials-virtual-machine-and-more/