Almost a catalogue of the new, innovating industries--and therefore an excellent companion to Rodger Bridwell's more generalized High-Tech Investing (p. 92). Toney is manager of a mutual fund that specializes in high-tech issues; Tilling is personal-computer columnist for the New York Times (and co-author of Donoghue's Complete Money Market Guide). Emphasizing the need for accurate information, they present a series of detailed, largely jargon-free appraisals of emergent enterprises: genetic engineering, robotics, custom semiconductor circuits, cellular/mobile radio, fiber optics, office automation, personal computers, applications software, data-base services, medical systems, military hardware, etc, Each evaluation includes a listing of the competing concerns (complete with addresses, corporate contacts, and capsule analyses), securities analysts who follow the field, important information sources (trade publications and major meetings), and unhedged conclusions. ""Look but don't touch is probably the best investment approach to genetic engineering companies for the next couple of years,"" warn Toney and Tilling, anticipating a shakeout. And despite the overcrowded broadcast spectrum, they're less than bullish on cellular/mobile radio: ""the market, like so many others in high technology, is not really in existence."" Further, they observe, pure plays may be hard to come by: Metromedia, one of their key corporations, recently acquired three small manufacturers of electronic paging gear. Re diagnostic equipment, they point to the problems posed by stiff health-care regulation. This scrupulous attention to pitfalls as well as opportunities prevails throughout the directory sections. Although much of their material will sooner or later be overtaken by events, Toney and Tilling have produced a wide-ranging reference/advisory work of real value to anyone considering high-tech commitments.