Books about the same subject are assigned the same shelfmark number. You'll find the number on the spine of each book. Here is a selection of shelfmarks for Product and Furniture Design:
Car Design 629.222
Design Product Innovation 658.5752
Furniture Design 749
Packaging Design 688,8
Product Design 745.2
Library Search is generally the best starting point for finding ebooks in any discipline. However you may find these collections useful to explore.