Katie Holmes Has Found Her Wedding Dress -- OMG!

Sometimes it's easy to forget that only 18 months ago, Katie Holmes, 27, was best known for Dawson's Creek.

Already 40 minutes late to the Yves Saint Laurent fashion show in Paris on October 5, the actress stepped out of a limo with new BFF Victoria Beckham and was greeted by a gaggle of photographers. But she wasn't looking for couture for her nuptials to Tom Cruise.

"I'm picking clothes for my closet," Holmes told Us Weekly, adding, "I've already chosen my wedding dress."

The designer? She wouldn't say (though Vera Wang and Karl Lagerfeld are rumored, they won't comment), but others are definitely guessing. No really, they are. For serious.

"She's a classic beauty, so I think she'll go with Armani," stylist Jennifer Rade tells Us.

Suggests stylist Phillip Bloch, "I think it should be off-white with a plunging neckline."

T.H. Gossip is betting on K-Mart, actually.

But no matter which dress Holmes has chosen, one thing is certain: She and Beckham will always have Paris. "I'm having so much fun," Holmes, who left Cruise and possibly fake and Asian daughter Suri Cruise in Beverly Hills, told Us. "It's amazing!"

Her glitzy itinerary began at YSL. Then the friends, who met last year, feasted on fish at the Place de la Madeleine and went to a party at the home of mogul Mohamed Al Faed.

The two pressed on the next day, hitting the Chanel and Giambattista Valli shows.

"Katie saw a black dress on the Chanel runway and mouthed to Posh, ‘I like that,'" says an insider.

At 1:30 a.m., they hit a Chanel party at the VIP Room, where Holmes glowed in a camel coat, despite the heat.

"Katie is so confident and glamorous now," says a source. "Tom has been good for her."

Sure. And K-Fed has been good for Britney.