If I’m understanding you correctly, you first need to set up your attributes. Catalog > Attributes > Manage Attributes. You’ll create the attribute, for say, Manufacturer, by adding a new attribute. You’ll name it something easy for you to remember (i.e., manufacturer_vehicle) and fill out the rest of the form as needed. I’d assume you would want to make the manufacturer a dropdown (if it’s only one item it could apply to) or a multiple select (if it could apply to more than one type of vehicle) input area so you don’t have mistakes based on people not knowing how to properly spell foreign manufacturer names. Just input all the manufacturers for whom they provide products (i.e., Honda, Audi, Ford). Don’t forget to actually name the attribute under “Manage Label/Options” on the left.
You’ll want to ensure that your new attribute falls into the attribute set you’ll be using for the products. You can manage these under Manage Attribute Sets from the same menu.
It is only then that you’ll want to create your products. Your attribute should appear as a field when you create your product if you selected to use the right attribute set just after you created the new product.
You can find more about attributes and attribute sets in the knowledge base if you want more detailed info.
Also, don’t forget that your end users may not know how to spell foreign manufacturer names either and you’ll want to add common mispellings to the key words (meta information) for the individual product to ensure it remains fully searchable.
I hope that answered your question. All the info is really in the knowledge base, but I thought you might just be unsure where to start.