Spyros Makridakis, Steven C. Wheelwright, and Rob J. Hyndman
Third Edition, 1998, John Wiley & Sons, Inc.
This text has stood the test of time, being in its third edition, and provides a reasonably comprehensive exposition of forecasting. There is a strong emphasis on time series models and all time series used in the book are available on the internet, along with 3003 series used in the most recent of a sequence of forecasting competitions.
Topics covered include:
The major omission for a comprehensive text is methods for new product forecasting - such as diffusion models and discrete choice models.
The webpage for the book is www.maths.monash.edu.au/~hyndman/forecasting/