Doug,
I see that you are local so the easiest thing to do would be to visit us in person.
When you arrive you simply tell us what you're looking for and we will track it down. If you don't already have a list of PA manufacturers, we can get you one.
Our library is a closed stack system so we will pull boxes and folders for you. Our literature files will contain sales literature, ads, manuals, photos and usually some periodical articles as well. Our Dunwoodie files will contain a large amount of periodical copies from contemporary sources.
In addition to traditional automobile manufacturers, we will also have files on race events, tracks, coach builders, auto shows and more.
You can stay all day if you'd like, we are open Monday-Saturday 8am-4pm. The only thing you will pay for when you visit us on site will be photocopies or scans.
Visiting the library is pretty painless. See you soon!
-Chris
Chris Ritter, Librarian
AACA Library & Research Center