A new agent, Tanya McKinnon at Mary Evans, has just landed her first big deal -- and it turned out to be a proposal by a former colleague at Nina Collins Associates, a scouting agency. The book is by ex-scout and now Newark Star-Ledger journalist Stephanie Stall, all of 26 years old, and it was preempted by Tom Spain at Dell/Delacorte for what McKinnon described as a "healthy six figures" for hard/soft. The book, tentatively titled Broken Homes, Broken Hearts, is an analysis, complete with many interviews, of the impact on the lives of adults whose parents divorced during their childhood. "I remember her reader's reports, and I knew she was a terrific writer," said McKinnon. The book, in which 14 publishers had expressed an interest, was sold to Spain on the basis of a 40-page proposal.