'Stalker Sarah' Celeb Pic Poser Reveals Dream Get

She's a 16-year-old California girl living the Hollywood dream.  She attends red carpet events, runs into celebrities like Miley Cyrus in her neighborhood and teen idols like Justin Bieber know her by name.

Since she started taking pictures with celebrities four years ago, "Stalker Sarah," as she is affectionately known, has amassed a celebrity photo album on Flickr.com with more than 4,600 photos.

Click HERE to see some of Sarah's favorite photos with the stars.

But even after posing with thousands of A-listers - from Brad Pitt and Angelina Jolie to Julia Roberts, Kim Kardashian and even Oprah - there is still one star she has her eyes on.

"Britney Spears," Sarah said today on " Good Morning America."  "I see her a lot and I have met her and I have talked to her but it's another one of those situations where it's at the park or she's with her kids and just not approachable."

That non-aggressive approach not taken by most paparazzi is the reason Sarah says she's been able to snap so many pics and earn the stars' trust.

"I always know the right situation," she said.  "So normally if I don't think it's going to be good for them, if I don't think they look right or I don't think they're going to want to take a picture, I just don't ask."

"I've been in a lot of really private situations with people where I don't even ask for a picture," said Sarah, also noting that stars like Justin Bieber recognize if she's grown or if something has changed in her appearance.   "I see Miley around the neighborhood.  I see Hilary Duff walking her dog all the time.  And I hadn't even had a picture with Hilary Duff yet, and she's one of my favorites.  But I'm like no she's walking her dog."

Sarah has become such a star herself that she goes just by her moniker, "Stalker Sarah," and does not reveal her last name, going only by "Sarah M."  She doesn't reveal many personal details, other than giving credit to the man who has made her celebrity photography hunt a possibility, her dad.

He was the one who encouraged her to take her first celebrity photograph - with actor Robert Hays - when the pair ran into him at an arcade.

"I knew him [Hays] as the dad from "Homeward Bound,"" Sarah said.  "My dad liked "Airplane" [another Hays' film] and he happened to have a camera in the car so I took a picture with him. "

That was when Sarah was 12 years old.  Her dad made a deal with her and, four years later, she's still snapping away.

"As long as I got straight A's in school he would take me to every event that he possibly could," Sarah said.  "I got straight A's and he had to keep that deal."

Sarah now has the photo-taking routine down to a science.  In each photo she stands to the right of the celebrity, always with the same expression - a calm smile - and her trademark uniform of a black leather jacket, a band t-shirt, glasses and heavy eyeliner.

For young "Stalker Sarah" wanna-bes, the photog has simple advice.

"Just be respectful," she said.  "Just go up and ask.  Don't run up them.  It's not going to work."