Catholic Encyclopedia: St. Peter Damian
Cardinal, Doctor of the Church. Died in 1072. Biographical article.
For All the Saints: Peter Damian
Overview of the saint's life and character.
Patron Saints Index: Peter Damian
Profile. Never formally canonized, although he is a Doctor of the Church. With links.
Peter Damian, Saint
Short biographical entry in the Columbia Encyclopedia.
Sacred Heart Parish: St. Peter Damian
Brief, entertaining, biographical sketch.
Saint Peter Damian, or of Damian, Cardinal, Bishop
From Alban Butler's Lives of the Saints.
Vietnamese Eucharistic Youth Society: St. Peter Da
The story of his life, suited to children. Formatting can make this hard to read.