| Celebrity | Character | Season(s) | Episode(s) |
|---|
| April Scott | Model | 1 | Talk Show |
| Charlotte Ayanna | Joanne | 1 | Date night |
| Val Kilmer | The Sherpa | 1 | The Script and the Sherpa |
| Nadine Velazquez | Janeen | 1 | New York |
| Scarlett Chorvat | Carol | 1 | New York |
| Doug Ellin | The Director | 1, 2, 6 | New York; Oh, Mandy; Scared Straight; Give a Little Bit |
| Holly Valance | Leanna | 2 | My Maserati Does 185 |
| Bai Ling | Li Lei | 2 | Chinatown |
| Matt Dallas | Male Model | 2 | Chinatown |
| Sarah Carter | Cassie | 2 | The Sundance Kids |
| Dale Dye | Scuba Instructor | 2 | Oh, Mandy |
| Chad Muska | Surfer | 2 | Oh, Mandy |
| Rainn Wilson | R.J. Spencer | 2 | I Love You Too |
| Anna Maria Horsford | Saigon's Mother | 2, 3 | Good Morning, Saigon; I Wanna Be Sedated |
| Mercedes Ruehl | Mrs. Chase | 3, 5 | Aquamom, Return to Queens Blvd. |
| Amanda Righetti | Jewelry Store Clerk | 3 | Aquamom |
| Malin Akerman | Tori | 3 | Three's Company, Strange Days |
| Cameron Richardson | Lindsay | 3 | Strange Days |
| Ken Jeong | Coffee Shop Manager | 3 | The Release |
| David Paymer | Sammy Kane | 3 | I Wanna Be Sedated |
| Lindsay Sloane | Nicole | 3 | I Wanna Be Sedated |
| Dante Basco | Jimmy/Fukijama | 3 | What About Bob? |
| Brian Tee | Jimmy's Bodyguard | 3 | What About Bob? |
| Will Sasso | Jay Lester | 3 | Dog Day Afternoon |
| Artie Lange | Scott Segil/Ari's Fraternity Brother | 3 | Gotcha! |
| Leslie Bibb | Laurie/Scott's Fiancee | 3 | Gotcha! |
| Michael Lerner | Joe Roberts | 3 | The Resurrection |
| Dan Castellaneta | Andrew Preston | 4 | The First Cut is the Deepest |
| Lisa Rinna | Donna Devaney | 4 | Malibooty |
| Mini Andén | Samantha | 4 | Malibooty |
| Stephen Tobolowsky | Mayor of Beverly Hills | 4 | Sorry, Harvey |
| Bob Balaban | Doctor | 4 | The Dream Team |
| Louis Lombardi | Cousin Ronnie | 4, 5, 6 | The WeHo Ho, Return to Queens Blvd., One Car, Two Car, Red Car, Blue Car |
| William Forsythe | Private Investigator/Eddie Lapowski | 4, 6 | The Day Fuckers, Scared Straight |
| Shanna Moakler | Kelsey/Blind Date | 6 | The Day Fuckers |
| John Heard | Richard Wimmer | 4, 7 | Snow Job, Tequila Sunrise |
| Melyssa Ford | Sexy Flight Attendant | 4 | No Cannes Do |
| Kim Coates | Carl Ertz | 5, 8 | Fantasy Island, One Last Shot |
| Giovanni Ribisi | Nick | 5 | Unlike a Virgin; Fire Sale |
| Kevin Pollak | Bob Levine | 5 | The All Out Fall Out |
| Fran Drescher | Mrs. Bob Levine | 5 | The All Out Fall Out |
| Jason Isaacs | Fredrick "Freddie Loventon" Line | 5 | Gotta Look Up to Get Down |
| Daniella van Graas | Natasha | 5 | Gotta Look Up to Get Down |
| Peter Stormare | Aaron Cohen | 6 | The Sorkin Notes, Security Briefs |
| Nicky Whelan | Air Hostess | 6 | Give a Little Bit |
| Jeff Garlin | Roger | 7 | Dramedy |
| Carrie Fisher | Anna Fowler | 7 | Tequila and Coke |
| Bob Odenkirk | Ken Austin | 7 | Porn Scenes from an Italian Restaurant |
| Ethan Suplee | Bartender | 7 | Porn Scenes from an Italian Restaurant |
| Tommy Gunn | Porn Vince | 7 | Lose Yourself |
| Blake Anderson | Donny | 8 | One Last Shot |
