Theory of Elasticity by Timoshenko and Goodier

Although I know it is not very original, I am recommending Timoshenko's Theory of Elasticity textbook. I find this book useful because it solves many classical solid mechanics problems without assuming the reader has a strong background in the subject (like me). When I am having difficulty with a homework problem, I turn to the index and it usually directs me to a section of the book directly related to the problem, or sometimes even the solution itself. Many parts of the book complement the course, such as the chapters "Plane Stress and Plane Strain" and "Analysis of Stress and Strain in 3 Dimensions."

The book starts with basic definitions and derivations of stress and strain, then applies these equations to solve problems in different coordinate systems. It also includes chapters on more specific topics, like torsion and thermal stress.

Here is the link for the Amazon book review.