In November, when the “save the date” was circulated for Prince William and Kate Middleton’s wedding, Elena Nachmanoff immediately booked a trip to London. She was going shopping — for royalty experts.

Nachmanoff, the executive in charge of talent for NBC News, knew what she wanted: an eminent British historian; a tabloid editor with deep knowledge about the royal family; a person who played a part in Princess Diana’s wedding 30 years ago. And she knew that other television networks wanted the same.

Because every network will be sharing the same camera feeds of the royal wedding on Friday morning, they have competed fiercely to sign up on-air talent in an attempt to make their hours and hours (and hours) of coverage stand out.

The most sought-after pundits have been signed to long-term contracts worth over $100,000; some even have deals with several outlets. The author of one book about the couple, Katie Nicholl, was the subject of a bidding war; she will be simultaneously working for ABC News, CNN’s “Piers Morgan Tonight” and the entertainment newsmagazine “Extra.”

The networks opened their wallets partly out of necessity: there is a long history in Britain of people being paid for interviews, and of giving short- and long-term contracts to experts is one way to meet that expectation. Fortunately, there is no shortage of talent to pick from in England, where reporting, gossiping and opining on the royal family is a full-blown industry.

But the costs have quickly added up for network news divisions, some still understaffed after years of cutbacks. Having sold special advertising packages for the event, networks are betting viewers are as interested in the wedding as their news anchors and producers evidently are.

As soon as the wedding date was set, “you would be shocked by how many emails we got from agents pitching their client as the royalty expert because they once saw Prince William, or once met Kate Middleton, or have once had dinner in the same restaurant,” said Rob Silverstein, executive producer of “Access Hollywood,” which is moving to London for a week.

Hollywood agencies including WME, CAA and ICM not only pitched experts for the wedding day, they sold what were effectively packages of experts for the television documentaries that are leading up to the ceremony.

“As long as you have an English accent,” Silverstein joked, “you’ll work.”

The pitches have not stopped, said Brent Zacky, a vice president at TLC, recounting a New York agent who pitched a “wedding expert” to him just last week. “There’s last-minute jockeying going on,” he said, even for one-time guest appearances.

The guest booking wars “have been ferocious,” said Piers Morgan, the CNN anchor.

But for the most part, each network’s plans are firmly in place. Along with A-list anchors, there will be Britons (the reality show host Cat Deeley will be on CNN), celebrities (Goldie Hawn will be on ABC’s “The View”) and journalists who covered Princess Diana’s wedding in 1981 (the former “Good Morning America” co-host Joan Lunden will be on Fox News).

TLC hired Amanda Byram, a native of Ireland who now lives in Britain and hosts television shows there, because “it’s important to have a local voice alongside our American voices,” Zacky said, echoing executives at other networks.

Those executives said in interviews that they doubted specific experts would actually sway the ratings on the wedding day.

“For the most part, this is a festivity that you don’t see a lot in life, so you just let it speak for itself,” said Bill Shine, an executive vice president at Fox News. But there are still hours of air time to fill before and after the ceremony.

“The palace has said that no friends can talk, so we have to rely on our knowledge, on our correspondents’ knowledge and experts in different fields,” said Barbara Walters, who will be co-anchoring with Diane Sawyer on ABC. On Friday afternoon, Walters was packing her bags for London, since many American news programs and entertainment shows will be in royalty mode starting on Monday.

After her first trip in December, Nachmanoff was back in London at the end of February to firm up NBC’s deals with experts like Camilla Tominey, the royalty editor for the Daily Express newspaper, and Andrew Roberts, the historian.

Perhaps NBC’s biggest coup was signing a long-term contract with Ben Fogle, a British television host who traveled in Africa with Prince William last year and who will be attending the wedding. (He will be hurrying to a camera position outside Westminster Abbey to recount his attendance afterward.) NBC calls Fogle a “special correspondent” and says he will stay on at least through the Summer Olympics in London next year.

No one would comment on the costs of all this expertise, citing confidentiality, but privately some agents and executives said thousand-dollar appearance fees for a segment were far more common than the six-figure salaries that “special correspondents” have received.

ABC’s biggest booking was probably Nicholl, whose book “William and Harry: Behind the Palace Walls” was published a week before the wedding date was announced. Like Fogle, Nicholl has been deemed a “special correspondent.”

ABC’s other contributors will include Tina Brown, the Newsweek and Daily Beast editor, who has a long-term contract with “Good Morning America;” one of Princess Diana’s bridesmaids, India Hicks; and a former press secretary for Prince William, Colleen Harris.

CBS, which is spending less than NBC or ABC to cover the wedding, has fewer contributors on its payroll. Its top “royal contributor,” Victoria Arbiter, who was raised in Britain but now lives in New York, also has deals with CTV in Canada and Channel 7 in Australia.

Among other experts working for several outlets is Morgan’s wife, Celia Walden, who writes for The Daily Telegraph. She will be appearing on NBC and “Extra” in the United States as well as on ITN in Britain.

Piers Morgan, who is British, said what he wants out of his guests on “Piers Morgan Tonight,” his 9 p.m. show on CNN, are personal stories and anecdotes. He said he would be recalling a private lunch he had with Princess Diana and Prince William when the prince was 13 years old. Of the bookings, he said, “It’s less about A-list faces. It’s ‘Do they know the royals or not?”’

The royal couple’s closest friends, presumably, will be at the wedding, not at the multistory media complex beside Buckingham Palace.

And that is partly why producers like Silverstein, of “Access Hollywood,” are having fun with the affair — and with the appointed experts who will be crowding onto television to talk about it. In a nod to Harry Potter, Silverstein has called his in-house expert, Neil Sean, a “royal wizard.”

“There are royal wizards everywhere,” Silverstein exclaimed. “They truly materialize anywhere you want them.”

© 2011 The New York Times Company