multiple .gitignore and friends in same workdir possible?

Hi,

while trying to move our Windows people from VSS to git i am
facing the following problem:

I want to have two (or three) git repos wich all share the
same working directory (this is manageable by environment variables),
one for the real source files and the other for 3'rd party binaries 
(*.dll, *.lib + perhaps include files for those)
and perhaps a third one for debugging symbol files (*.pdb and such)

In order to have .gitignore (and .gitattributes) files versioned
and also distributed on git clone they need to be inside the
work dir. Unfortunately the sources and binaries are co-located
inside the work dir subfolders - for historic reasons.

So i would like to have a mechanism to be able to specify different
filenames for .gitignore and .gitattributes  without having to
recompile git, perhaps by an environment variable.
(e.g by a suffix like .gitignore.src .gitignore.bin etc)

Is this currently possible or am I missing something? It would ease
my task a lot. 

Greetings,
Konrad