You can buy tracts from various companies, or from your local Christian bookshop.
The material I use ranges from 1p to £1. But a soul is priceless. “For God so loved the world that He gave..." We are just "sowing the seed, others will water it and God will give the increase." "Cast your bread upon the waters for after many days it will return unto you".
Sometimes you can buy a sample pack of all the tracts from a company, which is a good way to find out the ones that you like. Others send them for free!
You may want to ask your friends to chip in some money; some companies reduce the cost for bulk buying. Ask your parents, youth leader, pastor or local evangelist for advice.
Often with tracts you rarely see the results, but it does work. It is God's word that changes people, and I have heard of several testimonies of people reading a tract and getting saved. I personally have been doing this since 1996.