It might seem as if TV news-magazine anchors Diane Sawyer, Barbara Walters, and Katie Couric are constantly competing for the Tonya Hardings and Lorena Bobbitts of the world. But when PrimeTime Live's Sawyer became the prize in a high-stakes bid to woo her away from ABC, Sawyer counted on input from the good ol' girls. ''Diane called and talked to me about what I thought of the whole idea,'' says NBC's Couric, whose network reportedly offered Sawyer her own four-night- a-week magazine show and backup duties on the evening news. ''Having her work here would have changed a lot of things, and change is unsettling to everybody. But I could see by the end of the conversation why everybody is in love with her.'' CBS reportedly promised Sawyer a Nightline-type news-analysis show to follow the CBS Evening News. And Fox chief Rupert Murdoch, who recently lured football commentator John Madden from CBS to complement his deal with the National Football Conference, is said to have dangled a $7 million-$10 million salary as well as a post-football magazine show that would go head-to-head with 60 Minutes. To keep Sawyer from jumping networks, ABC countered with a $6 million-$7 million salary, the promise of airtime on at least three prime-time shows (Day One, PrimeTime Live, and ABC's new newsmagazine, Turning Point), and a ! personal plea from Walters. ''I called Diane and said, 'I hope you'll stay. It's best for you and for all of us,''' says the 20/20 cohost, who will alternate with Sawyer as anchor of Turning Point, which debuts March 9. ''I told her, 'Let's try to find ways of working together. Maybe one day we'll do some specials together.''' Sawyer's ample salary makes her TV's second-highest-paid newswoman, just behind Walters and her $7 million-plus paycheck. But will it set off a chain reaction? ''I would assume Barbara's on the phone saying, 'I want more too,''' says former NBC News chief Reuven Frank. Observes Washington Post TV critic Tom Shales, ''This is one of those pivotal moments where suddenly the prices all go up. It's like raising the interest rate.'' Couric, who would have been the big loser if Sawyer had chosen NBC, may now stand to benefit the most from the price war: She's currently negotiating her contract with the network. ''As you see salaries escalate, people say, 'What about me?''' admits Couric. Is she one of them? ''I was taught it's tacky to talk about money.''