The main source, such as it is, is Volo's Guide to the Sword Coast. Additionally, I'd add some of Elaine Cunningham's novels to this listing... most notably Elfshadow, since a great deal of the earlier portions of the book feature Evereska.
You can find some info here. I'm not sure if it is canon, though.
"Goodness is not a natural state, but must be fought for to be attained and maintained. Lead by example. Let your deeds speak your intentions. Goodness radiated from the heart."
The Paladin's Virtues, excerpt from the "Quentin's Monograph" (by Ed Greenwood)