Cobb grew up in Demopolis, Marengo County, and was inspired to pursue writing by his high school English teacher, Wynell Gantt. He earned his bachelor's degree at Livingston University in 1961 and a master's in creative writing at Vanderbilt University in Nashville, Tennessee in 1963. He began teaching Southern literature at Montevallo that same year and remained on the faculty until his retirement in 2000, including 13 years as "writer-in-residence".
Cobb has also written six plays, three of which (Sunday's Child, A Place of Spring and Early Rains) were staged at Herbert Berghoff's Playwright's Studio in New York in the 1980s.
Cobb's 1964 story "The Stone Soldier" won the national "Story of the Year" award from Story magazine. His 1992 novel, A Walk Through Fire, was nominated for a Pulitzer Prize. Somewhere in All This Green, his 1999 collection of short stories, was named "Book of the Year" by the Alabama Library Association. He was given the Harper Lee Award for Alabama's distinguished writer at the Alabama Writer's Forum in 2007.
Around the same year Cobb began suffering from normal condition hydrocephalus, a build-up of fluid in the brain. It took three years to make the proper diagnosis, during which time he suffered vertigo and difficulty concentrating. He expected to be unable to continue his writing career, but, after surgery, his symptoms began fading immediately and he resumed working. He and his wife, Loretta, also a writer and academic, reside in Montevallo.
- Cobb, William (1984) Coming of Age at the Y. Tuscaloosa: Portals Press
- Cobb, William (1987) The Hermit King. Tuscaloosa: Portals Press
- Cobb, William (1992) A Walk Through Fire. New York: W. Morrow and Co.
- Cobb, William (1995) Harry Reunited. Montgomery: Black Belt Press
- Cobb, William (1999) Somewhere in All This Green: New and Selected Stories
- Cobb, William (1999) A Spring of Souls. Montgomery: Black Belt Press
- Cobb, William (2001) Wings of Morning. Birmingham: Crane Hill Publishers
- Cobb, William (2010) The Last Queen of the Gypsies. Birmingham: Crane Hill Publishers
- Ryan, Shawn (December 3, 1995) "Author William Cobb Keeps His Quiver Full of Different Arrows." Birmingham News
- Gamble, Danny (Spring 2007) "A Sense of Place: William Cobb Wins 2007 Harper Lee Award." First Draft. pp. 2-3.
- Carlton, Bob (October 19, 2010) "Montevallo author William Cobb beats health scare, publishes his seventh novel." Birmingham News