| Person | Type | Job | Role(s) | Episodes |
|---|---|---|---|---|
 Ryan Seacrest | Crew | Creator | Creator | |
 Adam Brody | Cast | Actor | Self - The O.C. | 1 |
 Adam Sandler | Cast | Actor | Self | 1 |
 Aisha Tyler | Cast | Actress | Self | 1 |
 Alan Dale | Cast | Actor | Self - The O.C. | 1 |
 Alicia Keys | Cast | Actress | Self (performance) | 1 |
 Andrew Lawrence | Cast | Actor | Celebrity Courtyard Correspondent | 1 |
 Anne Hathaway | Cast | Actress | Self | 1 |
 Anthony Anderson | Cast | Actor | Self | 2 |
 Antonio Sabàto, Jr. | Cast | Actor | Self | 1 |
 Arsenio Hall | Cast | Actor | Self | 1 |
 Ashley Scott | Cast | Actress | Self | 1 |
 B-Real | Cast | Actor | Cypress Hill - Performer | 1 |
 Barry Manilow | Cast | Actor | Self - Performer | 1 |
 Beau Bridges | Cast | Actor | Self | 1 |
 Ben Stiller | Cast | Actor | Self | 1 |
 Bonnie Hunt | Cast | Actress | Self | 1 |
 Breckin Meyer | Cast | Actor | Self | 1 |
 Britney Spears | Cast | Actress | Self - Performer | 1 |
 Bryan Cranston | Cast | Actor | Self | 1 |
 Carmen Electra | Cast | Actress | Self | 1 |
 Caroline Dhavernas | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
 Catherine Bell | Cast | Actress | Self | 1 |
 Cedric the Entertainer | Cast | Actor | Self | 1 |
 Chris Klein | Cast | Actor | Self | 1 |
 Chuck Woolery | Cast | Actor | Self | 1 |
 Cindy Herron | Cast | Actress | Self - (En Vogue) Performer | 1 |
 Daisy Fuentes | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
 Dakota Fanning | Cast | Actress | Self | 1 |
 Dan Cortese | Cast | Actor | Self | 1 |
 Daryl Hannah | Cast | Actress | Self | 1 |
 David Arquette | Cast | Actor | Self | 1 |
 David Boreanaz | Cast | Actor | Self | 2 |
 Debbie Gibson | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
 Denzel Washington | Cast | Actor | Self | 2 |
 Diego Luna | Cast | Actor | Self | 1 |
 Dolly Parton | Cast | Actress | Self | 1 |
 Donald Trump | Cast | Actor | Self | 1 |
 Doris Roberts | Cast | Actress | Self | 1 |
 Doug Stanhope | Cast | Actor | Self | 1 |
 Dwayne Johnson | Cast | Actor | Self | 2 |
 Elisha Cuthbert | Cast | Actress | Self | 1 |
 Eliza Dushku | Cast | Actress | Self | 1 |
 Enrique Iglesias | Cast | Actor | Self - Performer | 1 |
 Esai Morales | Cast | Actor | Self | 1 |
 Flex Alexander | Cast | Actor | Celebrity Courtyard Correspondent | 2 |
 Frankie Muniz | Cast | Actor | Self | 1 |
 Gabrielle Union | Cast | Actress | Self | 1 |
 Gisele Bündchen | Cast | Actress | Self | 1 |
 Greg Kinnear | Cast | Actor | Self | 1 |
 Hilary Duff | Cast | Actress | Self | 1 |
 Isaac Hanson | Cast | Actor | Self - (Hanson) Performer | 1 |
 Jami Gertz | Cast | Actress | Self | 1 |
 Jamie-Lynn Sigler | Cast | Actress | Self | 1 |
 Janet Jackson | Cast | Actress | Self | 1 |
 Janice Dickinson | Cast | Actress | Self | 1 |
 Jason Bateman | Cast | Actor | Self | 1 |
 Jason Priestley | Cast | Actor | Self | 1 |
 Jean Louisa Kelly | Cast | Actress | Self | 1 |
 Jeff Gordon | Cast | Actor | Self | 1 |
 Jeff Probst | Cast | Actor | Self | 1 |
 Jennifer Garner | Cast | Actress | Self | 1 |
 Jennifer Love Hewitt | Cast | Actress | Self | 1 |
 Jermaine Dupri | Cast | Actor | Self - Performer | 1 |
 Jerry O'Connell | Cast | Actor | Self | 1 |
 Jerry Springer | Cast | Actor | Self | 1 |
 Jesse Bradford | Cast | Actor | Self | 1 |
 Joe Rogan | Cast | Actor | Self | 1 |
 Johnny Depp | Cast | Actor | Self | 1 |
 Jolene Blalock | Cast | Actress | Self | 1 |
 Jon Cryer | Cast | Actor | Self | 1 |
 Jon Foreman | Cast | Self - Switchfoot (singer) | 1 | |
 Josh Duhamel | Cast | Actor | Self | 1 |
 Kathie Lee Gifford | Cast | Actress | Self | 1 |
 Kathy Najimy | Cast | Actress | Self | 1 |
 Keiko Agena | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
 Kelly Rowan | Cast | Actress | Self - The O.C. | 1 |
 Kevin Bacon | Cast | Actor | The Bacon Brothers (performance) | 1 |
 Kevin Pollak | Cast | Actor | Self | 1 |
 Kiefer Sutherland | Cast | Actor | Self | 1 |
 Kim Delaney | Cast | Actress | Self | 1 |
 Kristen Stewart | Cast | Actress | Self | 1 |
 Kylie Minogue | Cast | Actress | Self | 1 |
 LeAnn Rimes | Cast | Actress | Self | 1 |
 Lenny Kravitz | Cast | Actor | Self | 1 |
 Linda Cardellini | Cast | Actress | Self | 1 |
 Lindsay Lohan | Cast | Actress | Self | 1 |
 Lisa Rinna | Cast | Actress | Self | 1 |
 LisaRaye McCoy | Cast | Actress | Self | 1 |
 Liza Snyder | Cast | Actress | Self | 1 |
 Lucy Lawless | Cast | Actress | Self | 1 |
 Mark Addy | Cast | Actor | Self | 1 |
 Marques Houston | Cast | Actor | Self | 1 |
Matthew Winter | Cast | Rooney (performance) | 1 | |
 Mekhi Phifer | Cast | Actor | Self | 1 |
 Melana Scantlin | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
 Melinda Clarke | Cast | Actress | Self - The O.C. | 1 |
 Melissa Joan Hart | Cast | Actress | Self | 1 |
Michael Bacon | Cast | Actor | The Bacon Brothers (performance) | 1 |
 Michael Bublé | Cast | Actor | Self - Performer | 1 |
 Michael Chiklis | Cast | Actor | Self | 1 |
 Michael Madsen | Cast | Actor | Self | 1 |
 Michelle Trachtenberg | Cast | Actress | Self | 1 |
 Mike O'Malley | Cast | Actor | Self | 1 |
 Mischa Barton | Cast | Actress | Self - The O.C. | 1 |
 Missy Elliott | Cast | Actress | Self | 1 |
 Molly Shannon | Cast | Actress | Self | 1 |
 Natasha Henstridge | Cast | Actress | Self | 1 |
 Navi Rawat | Cast | Actress | Self - The O.C. | 1 |
 Nelly Furtado | Cast | Actress | Self | 1 |
 Nia Vardalos | Cast | Actress | Self | 1 |
 Oprah Winfrey | Cast | Actress | Self | 1 |
 Pat Monahan | Cast | Actor | Self - Train (singer) | 1 |
 Paula Abdul | Cast | Actress | Self | 3 |
 Peter Gallagher | Cast | Actor | Self - The O.C. | 1 |
 Quentin Tarantino | Cast | Actor | Self | 1 |
 Rachel Hunter | Cast | Actress | Self | 1 |
 Reba McEntire | Cast | Actress | Self | 1 |
 Rebecca Gayheart | Cast | Actress | Self | 1 |
 Regis Philbin | Cast | Actor | Self | 1 |
 Rick Springfield | Cast | Actor | Self - Performer | 1 |
 Rob Schneider | Cast | Actor | Self | 1 |
 Robert Schwartzman | Cast | Actor | Rooney (performance) | 1 |
 Roma Downey | Cast | Actress | Self | 1 |
 Ron Perlman | Cast | Actor | Self | 1 |
Ryan Seacrest | Cast | Actor | Self - Host | 87 |
 Samaire Armstrong | Cast | Actress | Self | 1 |
 Sarah McLachlan | Cast | Actress | Self (performance) | 1 |
 Sasha Alexander | Cast | Actress | Self | 1 |
 Seal | Cast | Actor | Self - Performer | 1 |
 Sean Patrick Thomas | Cast | Actor | Self | 1 |
 Sela Ward | Cast | Actress | Self | 1 |
 Shad Moss | Cast | Actor | Self | 1 |
 Shannen Doherty | Cast | Actress | Self | 1 |
 Sharon Osbourne | Cast | Actress | Self | 1 |
 Sheryl Crow | Cast | Actress | Self (performance) | 1 |
 Smokey Robinson | Cast | Actor | Self - Performer | 1 |
 Stephen Collins | Cast | Actor | Self | 1 |
 Sting | Cast | Actor | Self | 1 |
 Taylor Hanson | Cast | Actor | Self - (Hanson) Performer | 1 |
Taylor Locke | Cast | Actor | Rooney (performance) | 1 |
Tim Foreman | Cast | Self - Switchfoot (bass) | 1 | |
 Tom Arnold | Cast | Actor | 1 | |
 Topher Grace | Cast | Actor | Self | 1 |
 Tori Amos | Cast | Actress | Self - Performer | 1 |
 Tracy Morgan | Cast | Actor | Self | 1 |
 Tyra Banks | Cast | Actress | Self | 1 |
 Usher | Cast | Actor | Self | 1 |
 Vanessa Williams | Cast | Actress | Self | 1 |
 Ving Rhames | Cast | Actor | Self | 1 |
 Zac Hanson | Cast | Actor | Self - (Hanson) Performer | 1 |
 Amanda Righetti | Cast | Actress | Self - The O.C. | 1 |
 Bobb'e J. Thompson | Cast | Actor | Self | 1 |
 Carmen Rasmusen | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
 Clay Aiken | Cast | Actor | Self - Performer | 2 |
 Jack Osbourne | Cast | Actor | Self | 1 |
Jasmine Trias | Cast | Self - American Idol contestant | 1 | |
Jerome Fontamillas | Cast | Self - Switchfoot (guitar) | 1 | |
 Jim Verraros | Cast | Actor | Celebrity Courtyard Correspondent | 1 |
Jimmy Stafford | Cast | Self - Train (guitar) | 1 | |
 John Mayer | Cast | Actor | Self - Performer | 1 |
 Justin Guarini | Cast | Actor | Celebrity Courtyard Correspondent | 1 |
 Kelly Clarkson | Cast | Actress | Self - Performer | 1 |
 Kimberley Locke | Cast | Actress | Self (performance) | 1 |
 Kimberly Caldwell | Cast | Actress | Celebrity Courtyard Correspondent | 1 |
Louie Stephens | Cast | Rooney (performance) | 1 | |
 Michelle Branch | Cast | Actress | Self (performance) | 1 |
 Ned Brower | Cast | Actor | Rooney (performance) | 1 |
 Nicole Richie | Cast | Actress | Self | 1 |
 Omarion | Cast | Actor | Self | 1 |
 Rachel Bilson | Cast | Actress | Self - The O.C. | 1 |
 Randy Jackson | Cast | Actor | Self | 4 |
 Raquel Castro | Cast | Actress | Self | 1 |
Ryan Sutter | Cast | Self - The Bachelorette | 1 | |
Scott Underwood | Cast | Self - Train (drums) | 1 | |
 Simon Cowell | Cast | Actor | Self | 3 |
 Solange | Cast | Actress | Self | 1 |
Steven Cojocaru | Cast | 1 | ||
 Susie Castillo | Cast | Actress | Self | 1 |
 Terry Dubrow | Cast | Actor | Self | 1 |
Trista Sutter | Cast | Actress | Self - The Bachelorette | 1 |
 Yoanna House | Cast | Actress | Self | 1 |
Chad Butler | Cast | Self - Switchfoot (drums) | 1 | |
Sen Dog | Cast | Cypress Hill - Performer | 1 | |
 Terry Ellis | Cast | Actress | Self - (En Vogue) Performer | 1 |
 Bob Guiney | Cast | Actor | Celebrity Courtyard Correspondent | 1 |
 Ruben Studdard | Cast | Actor | Self - Performer | 1 |
Baby Bash | Cast | Actor | Self - Performer | 1 |
 Drew Shirley | Cast | Self - Switchfoot (guitar) | 1 | |
 JC Chasez | Cast | Actor | Self - Performer | 1 |
 Deidra Roper | Cast | Actress | Spinderella - Celebrity Courtyard Correspondent | 1 |
Maxine Jones | Cast | Actress | Self - (En Vogue) Performer | 1 |
Jackie Thomas | Cast | Actress | Self | 1 |
 Adam Gontier | Cast | Three Days Grace (performance) | 1 | |
Neil Sanderson | Cast | Three Days Grace (performance) | 1 | |
Brad Walst | Cast | Three Days Grace (performance) | 1 | |
Barry Stock | Cast | Three Days Grace (performance) | 1 | |
Brandon Bush | Cast | Self - Train (piano) | 1 | |
| Person | Type | Job | Role(s) | Episodes |
