It would be interesting to know if he's actually ever read the Bible; many people, I find, who talk about the Bible's supposed faults have never really examined it seriously. You might ask your friend this (if you think he'll answer honestly), and you might also ask him to point out some of the "contradictions" he claims the Bible contains. (Your local Christian bookstore can suggest resources to answer his questions, if he's truly serious about them.)
But I suspect your friend's problem is deeper than this, and that his arguments about the Bible are only a smokescreen for something more serious. This is often the case, I've found, with people who aren't open to investigating the reliability of the Bible or examining the claims of Christ. Only Jesus could say, "I am the way and the truth and the life. No one comes to the Father except through me" (John 14:6).
What is your friend's problem? I suspect it's this: He simply doesn't want to face the fact that he needs God. In fact, he'd probably tell you he doesn't need God, and doesn't want anything to do with Him. He wants to run his own life, and he may even be afraid of what God might want to do in his life if he ever does believe in Christ.
Pray for your friend, that God will convict him of his need of Christ and open his heart to the truth. In addition, ask God to help you be a witness for Christ to him, both by what you say and by the way you live.