This book is an excellent introduction to special relativity. It very carefully distinguishes between the different types of time measurements. Also, it is one of the few introductory books that actually teaches the reader how to make use of spacetime diagrams. Advanced topics such as transformations of electromagnetic fields are not covered, but this this book will give you a strong basis for further study.
If want to get the same content for about $20 less, buy Unit R of Thomas Moore's Six Ideas That Shaped Physics. It seems that A Traveler's Guide to Spacetime became one volume in that series. Also, the Six Ideas book is in the second edition, but this book has not been updated.