Now the "Hills" stars want to get together with the Jolie-Pitts to make sure they're not mad.
"We wouldn't want to p-ss them off. She might steal Spencer -- you know, because she steals people's husbands!" Montag, 23, tells Playboy.com.
She goes on, "But seriously, we'd love to sit down and discuss fame with them. Consider this your formal invitation, Brangelina. Let's hang out sometime. We'll be SpeidiLina!"
Montag and Pratt, 26, also tell Playboy how they became authors.
"They always say, 'Write what you know,' and we know how to be famous. Plus, we're extremely giving people. What good is having all of this knowledge if you don't share it with others for the low, low price of $19.99, available online and at bookstores everywhere?" the couple says in a joint interview.
They continue, "As for how long it took, it was only as long as it took to dictate. This book didn't require much planning or thought from us. It's like if you asked Michael Jordan to write a book on how to dunk, or Bono to write one on how to be a rock star."
The two aren't "worried at all" that revealing their media strategies will have a negative impact on their fame.
"Our fame has never been about being liked. Being liked is fine, and we always love it when people come up to us and say nice things -- which happens more than you think -- but we're famous because we always keep people guessing," they say. "What's more surprising than a famous person actually telling people how they did it?"
So what's next for the couple, who wed in April and are currently fighting over whether or not to have children?
"We're going to adopt an African baby, date Vince Vaughn, shave our heads, pretend Spencer is trapped in a balloon and have octuplets," Montag says.