They were collected and canonized? What book is that in? Can you give me a reference?
The act of canonization itself is extra-scriptural (i.e. there is no "table of contents").
So your second question answers itself: What is one thing the Church has added that is not contained in the canon of Scripture? - The canon of Scripture.
I have no problem giving due’s where deserved, and I have said so in post past. From all I have read, the church in Rome did begin the collection of ancient manuscripts and became the receptacle of most early Christian writings, and since they considered themselves the church that Christ said he would establish here on earth, it is a given that they were the ones who felt the need to be in control of all writings, and through the Holy Spirit's guidance, made the final decision on the canon.
God had a job to get done, and you just happened to be the ones who had most of the writings, but remember, you had nothing to do with writing them, you simply collected them, and if you hadn't, God would have found someone else that would have.
I'll ask you a question, do you think the Catholic Church ever had any intentions of mass producing them in an everyday language, then distributing them to the world?
If it hadn't been for the reformation they would still be in Latin, and only your clergy would be allowed to own them.
By the time the Bible was canonized, and was beginning to be read by some, you had already established most of your doctrine, and there sure was no turning around then. Isn’t that ironical, the ones that God gave the honor of sifting through all the manuscripts and preserving the word for the whole Christian world, should be the ones who now reject it as final authority, and do as the Jews did, put tradition and human authority over the written word.
Mk 7:13 Making the word of God of none effect through your tradition, which ye have delivered: and many such like things do ye.