Paris and Ashlee Simpson's Ex!

Dressed in a green sexy mini dress, Paris Hilton celebrated St. Patrick's Day on March 17, with actor Josh Henderson by her side! "They couldn't take their eyes off of each other", a source tells Star. "Paris looked completely smitten with Josh. She just kept smiling and laughing at everything he said, like she was under his spell. They actually make a really good looking couple."

The twosome met up at Hollywood nightclub Area Saturday night, where they where later spotted leaving together in a friend's Hummer. "Paris and Josh sat in the backseat of the car by themselves for about 15 minutes," says the source. "It was just the two of them talking and flirting. I guess they wanted to have some alone time before heading to Paris' house where she had a St. Patrick's Day party."

Hilton's impromptu party at her Beverly Hills home brought out some close pals, including Nicole Richie and Brandon Davis.

Noticeably missing was Hilton's on again, off again boyfriend Stavros Niachros who was "no where in sight", says an eyewitness. "Paris was with Josh most of the night. She appeared to be having a lot of fun. The two were in the kitchen the entire night eating pizza and talking", a party-goer tells Star. Josh plays the hunky nephew of Nicollette Sheridan's character on Desperate Housewives. The Texan native, who is also working on a solo album, was Ashlee Simpson's boyfriend from 2002-2004.

Source