For general books about ESL, browse the shelves at the following Library of Congress (LC) Call Numbers:
PE1 - PE3729 in for English Language
PE1001-1693 for Modern English
PE1700-3602 for Dialects
PE3701-3729 for Slang etc.
The Library of Congress Classification System is used to organize books on the shelves, using 21 categories, labeled A-Z.