This Windows Communication Foundation (WCF) video examines how to configure a BizTalk receive location using the WCF-Custom adapter. This adapter is extremely flexible and allows you to customize features of security, message body extraction, behaviors, bindings, and to import/export configuration files.
Presented by Michael McKeown Length: 4 minutes 52 seconds
http://msdn.microsoft.com/en-us/biztalk/dd878388.aspx
Another important place to find a huge amount of BizTalk related articles is the TechNet Wiki itself. The best entry point is BizTalk Server Resources on the TechNet Wiki.