Filmmaker Mark Moskowitz, who earns a living making political commercials, turns his considerable skills of media persuasion to the nobler service of selling serious books. And with Stone Reader, he makes the sale. Specifically, the hard-driving and aggressively well-read Moskowitz conveys the power of ''The Stones of Summer,'' an unsung 1972 novel that affected him profoundly and has long been exiled in out-of-print oblivion.
The search to find out what happened to its author, Dow Mossman -- who never published another book -- launches Moskowitz on a quixotic cross-country adventure, simultaneously self-regarding and indefatigable, talking to editors, agents, and other writers about the terrors and pleasures of reading and publishing. It's ''Moskowitz's March,'' really -- in the tradition of Ross McElwee's wholly original 1986 pseudo-documentary ''Sherman's March'' -- and it ends in stirring victory: When the humble, gently defeated-looking author is found and thanked, it's hard not to weep in honor of one small battle won for the written word.