In response to your request, this link will provide a plethora of quotes from Augusine's work on the topic.
http://www.monergism.com/thethreshold/articles/onsite/augustinequotes.html
Some interesting quotes as well.....
Augustine
For them [the Pelagians], grace means the knowledge with which the Lord God helps us, by which we can know what our duty is. The true meaning of grace, however, is the love that God breathes into us, which enables us with a holy delight to carry out the duty that we know.
Augustine - Against Two Letters of the Pelagians, 4:11
Can you say, ‘We will first walk in His righteousness, and will observe His judgments, and will act in a worthy way, so that He will give His grace to us’? But what good would you evil people do? And how would you do those good things, unless you were yourselves good? But Who causes people to be good? Only He Who said, ‘And I will visit them to make them good,’ and, ‘I will put my Spirit within you, and will cause you to walk in my righteousness, and to observe my judgments, and do them’ (Ezek.36:27). Are you asleep? Can’t you hear Him saying, ‘I will cause you to walk, I will make you to observe,’ lastly, ‘I will make you to do’? Really, are you still puffing yourselves up? We walk, true enough, and we observe, and we do; but it is God Who He makes us to walk, to observe, to do. This is the grace of God making us good; this is His mercy going before us.
Augustine - Against Two Letters of the Pelagians, 4:15
"To will is of nature, but to will aright is of grace." - Augustine
"God bids us do what we cannot, that we may know what we ought to seek from him."- Augustine
"Grace alone brings about every good work in us."- Augustine
"Nature is common to all, but not grace."- Augustine
"The grace of God does not find men fit for salvation, but makes them so."- Augustine
"The nature of the Divine goodness is not only to open to those who knock. but also to cause them to knock and ask."- Augustine
"Let God give what he commands, and command what he will."- Augustine
"Grace does not destroy the will but rather restores it."- Augustine
"In some places God requires newness of heart [Ezek 18:31]. But elsewherre he testifies that it is given by him [Ezek. 11:19; 36:26]. But what God promises we ourselves do not do through choice or nature; but he himself does through grace."- Augustine
"Indeed, God requires faith itself of us; yet he does not find something to require unless he has given something to find."- Augustine
'Can we possibly, without utter absurdity, maintain that there first existed in anyone the good virtue of a good will, to entitle him to the removal of his heart of stone? How can we say this, when all the time this heart of stone itself signifies precisely a will of the hardest kind, a will that is absolutely inflexible against God? For if a good will comes first, there is obviously no longer a heart of stone.' - Augustine
"Since these things are so, everything that is commanded to human beings by the Lord in the holy Scriptures, for the sake of testing human free will, is either something we begin to obey by God's goodness, or is demanded in order to show us our need of grace to do it. Indeed, a person does not even begin to be changed from evil to good by the first stirrings of faith, unless the free and gratuitous mercy of God produces this in him…. So, therefore, we should think of God's grace as working from the beginning of a person's changing towards goodness, even to the end of its completion, so that he who glories may glory in the Lord. For just as no-one can bring goodness to perfection without the Lord, so no one can begin it without the Lord."
- Augustine, Against Two Letters of the Pelagians, 2:23