What would the Apple II GS made for Steve Wozniak
be worth? I do mean the actual, physical object!
Where would one place such an item? Thank you.

There are many computer museums, including this one at Coleman College in La Mesa, CA.

An excellent place might be The Smithsonian.

It's worth would likely have to be determined by an auction. Regardless of how much one thinks anything is worth, the real test comes when somebody is ready to buy it!