The Soul of a New Machine, by Tracy Kidder. New York: Avon Books. 293 pp.

''The Soul of a New Machine'' makes its appeal to the lay reader in the form of a nearly novelistic suspense story drawn from the actual development of a new high-performance computer at Data General Corporation in Westborough, Mass.

Kidder has written a painstakingly factual account of how a specific product - Project Eagle - was designed and built; an informal study of management and professional styles; and a layman's guide to computers and programming. To humanize his account, Kidder turns aside periodically for close-ups of key figures in his industrial drama. These vignettes are what give the book its novelistic flavor. Among these engaging protagonists are:

* The project manager

* The computer architect.

* The microcode specialist.

* The secretary.

The book provides a window on corporate life at a kind of frontier level, where reputations and fortunes can be made or lost almost overnight, because the designers of these electronic marvels are pushing, pushing all the time for yet another advantage in this lucrative and highly competitive market.