Almost any invention or scientific advance you could name has brought both good and evil to the human race and the Internet is certainly no exception. Nowhere is this seen more clearly than in the plague of pornography. It is an appalling blight on our society, and you are right to be concerned about it.
I frankly don't know the full solution; I doubt if any single action will bring this scourge to an end. I certainly would encourage you, however, to let your Internet service provider know of your opposition, and also your governmental representatives (both local and national). The Bible tells us to "seek the peace and prosperity of the city to which I have carried you" (Jeremiah 29:7) and one way we can do that in a democracy is to let our voices be heard.
The ultimate solution for this, however, is within the human heart. This is our real problem; as the Bible says, "each one is tempted when, by his own evil desire, he is dragged away and enticed" (James 1:14). That is why we need Christ, for only He can forgive us and change our hearts from within by His Spirit. Make sure of your commitment to Him, and then pray for our nation that we will turn to God before it is too late.