Austin was born in Providence, Kentucky. As her father was career military, she grew up in Germany and Japan, as well as the United States. She studied art and biology on an art scholarship at the Sacred Heart Dominican College in Houston, Texas, which closed in 1975. Her early influences include Edmund Dulac, Arthur Rackham, and N.C. Wyeth.
In the beginning of her career, she illustrated for fanzines, such as Energumen, Granfalloon, Aspidistra, and Science Fiction Review. She sold every piece of work entered in the 1969 Sci-Fi Worldcon in St. Louis, and then began accepting professional assignments. Her first two assignments were the first two Universe anthologies, which were edited by Terry Carr. She then became a regular artist for Zertex Magazine. Austin has illustrated books by Robert E. Howard, C. L. Moore, Andre Norton, Harold Lamb, Poul Anderson, Lewis Shiner, and Ursula K. Le Guin. A collection of her work, Alicia Austin's Age of Dreams, was published by Donald M. Grant, Publisher, Inc. in 1978.
She currently lives in Los Angeles, California.