If I have a product though I'm not sure if I want to build a new company around it, how do I go about researching the companies that are looking for new products?
Few things are as "sad" with companies in this country (and the world) than the ones who should be open to innovation and the independant inventor and yet are closed, indifferent, and/or unresponsive (ya listening Amazon!?!) .
Anyways, your question is well answered by Inventors Digest "Inventor Friendly Companies" and InventRight "Directory of Companies Looking for Inventions" ... they both have lists for you to grind upon (not sure about the designer part).
Best wishes to you!