The Internet Detectives series is up and running with this first installment introducing a handful of young e-mail pen pals from several countries. In England, Josh and Tamsyn volunteer to research how the Internet can be used at their school, newly online. With the aid of other Web surfers, the pair cracks a code and deciphers a boy's e-mailed call for help. A predictable, anticlimactic finale caps this adventure, which most middle graders will find quite tame. Curiously, given the timeliness of his tale's theme, Coleman occasionally trots out stiff, retread descriptions and dialogue, some of which could have come right off the pages of early Nancy Drew mysteries (e.g., the father of the teen in trouble ""was smartly dressed in a blue business suit. His dark hair was flecked with gray hair at the temples""). Some of the information provided about operating a computer and accessing the Internet may be too elementary for seasoned computer users likely to be drawn to the series. Still, relatively brief blocks of text that alternate with facsimiles of computer screens featuring the characters' e-mail messages make the pages especially reader-friendly for those accustomed to viewing the written word through a high-tech medium. The same keyboard-tapping cast returns in Escape Key, due the same month, to be followed by Speed Surf in December and Cyber Feud in February. Ages 8-12. (Oct.) FYI: An entry form for a sweepstakes featuring an Apple computer as a prize, is contained in both October books.