Living Waters is a website full of evangelism resources. A lot of resources are available for free. They also have resources for sale, including a selection of really unique tracts.
I recommend you check out Hell’s Best Kept Secret. It is a message from Ray Comfort about the non scriptural evangelism techniques that are often used today, and how they can often lead to false conversions . Below is a quote from the site about the message:
Why do 80-90% of those making a decision for Christ fall away from the faith? What is the principle that Spurgeon, Wesley, Whitefield, etc., used to reach the lost? Why has the Church neglected it? Don’t let anything stop you from listening to this incredible teaching.
I encourage you to check it out. You can read, listen, or watch it on their site.