Here are two sites (ja, auf Deutsch) I found about St. FDS.
* LEBEN VON UND MIT FRANZ VON SALES (1567–1622)
* Franz von Sales: Lexikon
The following three essays are fine expositions of Salesian spirituality.
* FRANCIS DE SALES, JANE DE CHANTAL AND THE MINISTRY OF LOVE by Wendy Wright, Ph.D.
[Francis and Jane] shared a distinctive vision, a spirituality we would call it today, which shaped their personal relationship to God and others and which profoundly influenced the way in which they exercised their leadership. The spiritual tradition which is their legacy to us is known as "Salesian." Its particular hallmarks are these: Jane and Francis believed the world to be the creation of a God whose most telling name is Love. This loving God and creation itself was best imaged for our two saints as a world of hearts. God's heart, overflowing in creative abundance gives birth to a world whose deepest impulse is to return to God in love. Thus human hearts, made in the divine image and likeness, are designed to know and love God. In fact, in the dense imagery of Salesian metaphor, God's heart "breathes," in and out, and our hearts' desires breathe in concert, in inspiration and aspiration, with the heartbeat of God.
* The Dynamics of Love by Susanne A. Kjekshus Koch
* St. Francis de Sales and the Universal Call to Holiness by Margaret S. Margeton
There is a certain beauty in holiness, and a certain holiness in beauty.