You must check out this great evangelistic tool offered by Desiring God Ministries. It is a 48 page softcover booklet specifically designed for evangelism, entitled For Your Joy. I have read through it, and it is just great. It deals with the gospel thoroughly as well as addressing some common hindrances to faith, such as the problem of pain and suffering. This booklet is very clear and direct, yet written in a warm, loving and personal way. You can read the whole booklet by previewing it.
Desiring God is offering these booklets at a greatly reduced cost when purchased in bulk. These would be great for giving to people you meet on a plane, or for coworkers. Churches could purchase them and give them to visitors. The opportunities for utilizing this resource seem endless.
Along these lines, Desiring God has produced a first class MP3 CD of 7 messages by John Piper that would also be useful for evangelism. Bulk discounts are also available for this resource, entitled Light and Heat.
(Jesus) said to him, “Go home to your friends and tell them how much the Lord has done for you, and how he has had mercy on you.” Mark 5:19 ESV