Her novels The Well of Fates (1993) and The Witches' Judgement (1994) concern a slave in the Viking era and are influenced by the Icelandic sagas.
She has also written a trilogy, historical fiction about Auður Djúpúðga (Aud the Deep-Minded), one of Iceland's most famous female settlers.
Vilborg's book Ástin, drekinn og dauðinn (On Love, Dragons and Dying) (2015) is her most personal story yet.
There she writes the story of her husband's journey with terminal brain cancer, and her first year as a widow, during which both her mother-in-law and her father died as well.
Some of her books have been translated and published in The United States, Egypt, Germany and Faroe Islands.