Certainly the Psalms are full of examples of asking God to remove evil people from the earth. However, Christ came and gave us a new way, a better way, of looking at such prayer:
You have heard that it was said, ‘You shall love your neighbor and hate your enemy.’ But I say to you, love your enemies, bless those who curse you, do good to those who hate you, and pray for those who spitefully use you and persecute you, that you may be sons of your Father in heaven; for He makes His sun rise on the evil and on the good, and sends rain on the just and on the unjust. For if you love those who love you, what reward have you? Do not even the tax collectors do the same? And if you greet your brethren only, what do you do more than others? Do not even the tax collectors do so? Therefore you shall be perfect, just as your Father in heaven is perfect. (Matthew 5:43-48)
Paul continues this theme in Romans 12:19-21:
Beloved, never avenge yourselves, but leave itto the wrath of God, for it is written, “Vengeance is mine, I will repay, says the Lord.” To the contrary, “if your enemy is hungry, feed him; if he is thirsty, give him something to drink; for by so doing you will heap burning coals on his head.” Do not be overcome by evil, but overcome evil with good. (emphasis mine)
Given these two pieces of Scripture (and the example of the Saints!), how can we call ourselves Christian and pray for the destruction of anyone, even the most heinous among us? Yes, we can pray that the oppression or danger caused by such people will end and come to pass, but that is markedly different than praying that God will damn someone or consign them to their just punishment (or at least "just" in our own mundane and sinful eyes)! Remember, the same Psalmist who wrote Ps. 68 (which I confess is among my favorites!) also wrote Ps. 129:3 :"If You, Lord, should mark iniquities, O Lord, who could stand?".
I guess what I'm getting at is the old adage "Hate the sin, love the sinner". Yes, we should see that someone who pimps out her daughter should not have the ability to do so ever again, but who are we to pray to God to damn such a person? We should be praying for her repentance and for God to have mercy on her immortal soul because her own actions will judge her before Christ Jesus, not our pithy prayers.