Any Makefile examples available - Preprocess files

[Jaye Speaks]

Question:  Do you know where I could find a collection of Makefile examples?
Question:  Do you know where I could find an example solution that is similar 
to the one I propose below?

Fact: I own a copy of the GNU Makefile book, have read and studied it, and 
still have questions.
Fact: I need some examples of Makefile based solutions to figure out how to 
accomplish my desired implementation of a Makefile build workflow.

Problem:  I have a master folder (along with child folders) of files that 
contain C-Preprocessor statements (IFDEF, etc.).  I want to utilize a Makefile 
to produce "processed" versions of the master files into the appropriate 
matching folder structure.

Folder:
\Makefile
\partnerA.h
\partnerB.h
\partnerC.h
\master\p\file1.src
\master\p\file2.src
\master\p\file3.src
\master\p\js\file4.src
\master\p\lib\file5.src

Desired workflow:
\gmake partnerA
\gmake partnerB
\gmake partnerC


Produced "processed" output:
\build\partnerA\p\file1.src
\build\partnerA\p\file2.src
\build\partnerA\p\file3.src
\build\partnerA\p\js\file4.src
\build\partnerA\p\lib\file5.src

\build\partnerB\p\file1.src
\build\partnerB\p\file2.src
\build\partnerB\p\file3.src
\build\partnerB\p\js\file4.src
\build\partnerB\p\lib\file5.src

\build\partnerC\p\file1.src
\build\partnerC\p\file2.src
\build\partnerC\p\file3.src
\build\partnerC\p\js\file4.src
\build\partnerC\p\lib\file5.src