Arnetia began her career shortly after entering high school.  Only 16 years old she landed a part on Broadway in "The Sign In Sidney Brustein's Window", starring Hal Linden.

After high school she enrolled at Bronx Community College, but left when she was invited to become Stephanie Mills' standby in the Broadway production of "The Wiz".  She was immediately hired to replace Debbie Allen in the Broadway musical, "Raisin".
Moving to California, she headlined a musical revue at Disneyland for two years. Developing a comedy nightclub act at the same time, she left the Magic Kingdom to tour many of the major clubs in the area. Between engagements, she appeared in the feature, "The Best Little Whorehouse in Texas", as well as "The Neil Sedaka Special", "ABC Presents Tomorrow's Stars"; and co-starred on an episode of NBC's "Quantum Leap".

A few years later she assumed her best-known stage role in Michael Bennett's hit musical, "Dreamgirls". Arnetia holds the distinction of being the only actress credited with portraying all three Dreamgirls. This lead to television guest-starring parts and her feature film breakout role as To-bel, in Paul Bartel's offbeat comedy, "Scene's From the Class Struggle in Beverly Hills. In 1991, television viewers were introduced, to Arnetia when she created the role of head nurse Annie Roland, for the NBC comedy "Nurses". True to her musical roots, Arnetia continues to sing as well as write.