You'd probably enjoy collections of radiator caps / hood ornaments / badges for vintage cars. Some time ago, I toured the Nethercutt Collection in southern California (Sylmar, CA) that had some cool radiator caps, etc. (and complete cars too, of course!)

In a quick google search, it looks like there's a number of auto museums around the country that include such vintage accessories.

Some of them are real works of art, both US and international autos from the golden age.