So, I'm in Chapter 11, pg 459.

I'm in the process of trying to connect to the BCS proxy via use of the BCS client runtime.

Now, I can find the Microsoft.BusinessData.dll. Thats easy enough.

But I cannot find the Microsoft.Office.BusinessApplications.Runtime.dll.

Nowhere to be found.
Nowhere on the system.
Its not even in the Windows\Assembly GAC. Thats where I've had to pull some of the DLLs before, but its not there.

Where do I find it/extract it?

The DLL can be located in:

C:\Program Files\Microsoft Office\Office14

But only if you have Microsoft Office 2010 installed.