These are my favorite books for caving and vicarious caving. Some of these may be out of print, but you can get them at the library or used on Amazon.
The Best How-To Books
Adventure of Caving - David McClurg
This book shows how to explore caves safely and softly. I checked this out of the library so many times as a kid, when they were retiring it, the librarian saved it for me. We followed every guideline in this book.
The amateur's guide to caves & caving: Skill-building ways to finding and exploring the underground wilderness
This has been out of print for a while, but it is available used on Amazon.
Caving Basics: A Comprehensive Guide for Beginning Cavers
A good first book. Things have changed, but the information is very good to get an overview of everything you need to know to go caving, focusing on safety and good cave conservation. It covers lights, helmets, clothes and caving equipment. It also gives you an overview on caves.
On Station - A Complete Handbook for Surveying and Mapping Caves
Want to map caves? Or find out what all of those letters and numbers mean in other books? This book has "everything a cave surveyor needs to know about surveying and mapping caves. It includes everything from gathering complete, accurate information to preparing a precise and attractive map for publication."
Underground Worlds: A Guide to Spectacular Subterranean Places
240 pages of great photos of some 50 different caves.
Speleology the Study of Caves
This is small book, but packed with information on how caves form. It's technical, but easy for anyone to understand.
The Wilderness Underground: Caves of the Ozark Plateau
The photos make this book worth owning. It has photos of every kind of cave and cave animals. It tells the story of caving from Native Americans to more current cavers.
Caves: Exploring Hidden Realms
Caves are the only truly unexplored places left. The author brings you on an "astounding journey into the wonders and hazards of caving."
This book has "hundreds of vivid, full-color images of places no large-format camera has ever been before and conveys the excitement, terror, and exhilaration of the world's vast and least accessible spaces."
Caving Accounts & History
The Caves Beyond: The Story of the Floyd Collins' Crystal Cave Exploration
"The Caves Beyond is a classic caving adventure story. There is no other caving book like it…" This tells the story of a caving expedition in 1954 that eventually led to joining the Flint Ridge Cave System with Mammoth Cave. The new edition has an index. I love a book with an index.
The Longest Cave
I would read anything Roger Brucker writes. This book really makes you feel like you are there through the years of effort that linked Flint Ridge and Mammoth Cave.
Beyond Mammoth Cave: A Tale of Obsession in the World's Longest Cave
I am reading this right now. My daughter bought it for me for our anniversary. (Great choice Jessica!) It is a great read. Very personal first-person accounts of what it is really like to cave. Whether or not you have ever caved, this is a really exciting book. I would read anything Roger Brucker writes.
Trapped!: The Story of Floyd Collins
Floyd Collins was trapped in a cave in southern Kentucky in early 1925 it became front-page news. It turned into America's first true media event. This book follows the efforts to save Floyd Collins and the media circus that surrounded it. This edition includes additional new information about the Floyd Collins story.
Grand, Gloomy, and Peculiar: Stephen Bishop at Mammoth Cave
This book (by Roger Brucker) is a carefully researched novel based on the true story of America's first great cave explorer at Mammoth Cave. Stephen Bishop was a mixed race slave famous for being one of the first Mammoth Cave explorers and guides.
Carlsbad, Caves, and a Camera
This is the story of Ray V. Davis, the first Carlsbad Caverns photographer. The photos are beautiful, but the story of cave exploration in the ‘30s is really exciting.
A Man Deep in Mendip: The Caving Diaries of Harry Savory 1910-1921
The journal and photos of Harry Savory, considered by many to be the finest photographer to have taken his camera underground. Almost 100 superb photographs, taken between 1910 and 1928 as well as maps and plans of the caves and drawings Savory commissioned from his artist friend John Hassall.
Caves and Caverns
This is a good introduction to caves for kids. It covers sea caves, lava caves, ice caves, and more. It makes caving exciting, but also encourages safe caving.
The Hidden World of Caves: A Children's Guide to the Underground Wilderness
This book is written for little kids and is very readable. It encourages safety. It has a glossary that gives good kid version definitions of cave terms.