I do not know where to find a call number

To find a print source (books, journals, maps, and government publications) you will need 4 things:

1. OMNI, the Library's one-stop search tool. Type keywords into the search box and click Search or Enter. On the results page, you can use a series of refinements including peer-review journals, books and articles. If you only want Print resources, choose Print/Physical Item
2. Library location and floor number: on each record for a print item, there will be a library location and a floor number
3. You will want to take down the Call Number
4. Check the availability

Image:

This library record for "The catcher in the rye" tells you the item is available and held on the 3rd floor. The call number is PS3537 .A426 C3 1951

While the call number appears horizontal in the record, on the book, the call number is vertical and can appear on the lower spine of the book or on the front cover, bottom left hand side.

For this call number it would appear as:

PS
3537
.A426
C3
1951

Watch this helpful video: Finding a book on the shelves

Learn more about the Library of Congress Call Number System.