Originally produced in 1998, the play kicked ... off the Lesbians in Theater program at the L.A. Gay & Lesbian Center in 2004. Lynch's other stage credits include Tales of the Lost Formicans, Ennui, and Waiting for Iggy.

She made her film debut in 1988 with a small role in the body-switching comedy Vice Versa. On television, she was in the Lifetime movie In the Best Interest of the Children and made numerous guest appearances on sitcoms. After some meager roles in Straight Talk, The Fugitive, and Fatal Instinct, she had the good fortune to join Christopher Guest's gang of improvisational comic actors. Her breakthrough role was butch Christy Cummings, the personal dog handler to trophy wife Sheri Ann Cabot (Jennifer Coolidge) in the 2000 mockumentary Best in Show.

Over the next two years, she played a government agent in the action movie Collateral Damage, a sarcastic nurse in the ABC medical comedy MDs, and a 1940s-style receptionist in the TNT movie The Big Time. In 2003, she reunited with the cast from Best in Show for the musical spoof A Mighty Wind. She performed her own music in the role of Laurie Bohner, the former porn star and member of the New Main Street Singers. In 2004, Lynch appeared in Sleepover, Little Black Boot, and The Californians.