When you find a physical book on the library website, write down its call number, and then go to the shelves.
To use call numbers, read them from the top down.
For example, here's how you'd find this book:
If you find an item that belongs to another library system, you may request it through Interlibrary loan (ILL).
To place an interlibrary loan request, you will need to create a free Simpson Library ILL Account.