I sell vintage science fiction books under another ID. Many of these do not appear in the eBay catalogue (Muse?).
If I don't find the book when I enter the ISBN #, I then try the title and author. This may get a number of items I have to winnow to find the right one.
If the book is still not there, I return to the original page and enter the (unlisted) ISBN again. Click on Search.Click on Search again.
Then a blue link appears in the text above the box for the number.
Click on it and a blank catalogue entry form appears.
Will this work for laptops? Darned if I know, but it may be worth trying.