Many companies, organizations, and individuals maintain websites where you can learn more about our industry and its technologies. These resources are free except where noted, though registration might be required. Since the Web is ever-changing, these sites may also contain links to other resources that evolved after I wrote this book. Of course, some of them may also have disappeared by the time you read this.
This amateur radio organization publishes many books about electronics, including an excellent primer, Understanding Basic Electronics, for $30. Their ARRL Handbook ($60 hardcover, including CD-ROM) is a 1,300-page technical encyclopedia, updated every year.