The so-called extra books (not chapters) are called the Deuterocanonical books that are used not only in the Catholic Church but also in the Eastern Churches. Too bad most Protestants reject it, because some of it contains or talks about things not believed by Protestants, such as praying for the repose of the dead and Purgatory.

http://en.wikipedia.org/wiki/Deuterocanonical_books

We pray to the saints and Mary, because we believe they are spiritually alive and enjoying the beatific vision of God in Heaven, and can intercede for us to God, just like any other humans who prays for us, but even better because the saints are special friends of God Himself. Just to be certain, we do not worship Mary or the saints in the same manner as we worship God, for even worship have varying degrees expressed in the following Greek terms:

Latria - the supreme worship due only to God.
Dulia - veneration due to the other saints
Hyperdulia - veneration due to the Blessed Virgin Mary (thus the addition of hyper because Mary is the most perfect model of all the saints)

Hope this helps.

Jesus is the ONLY mediator with the Father, but you seem to forget that Jesus is also God Himself. Mary and the saints can most certainly intercede for us to Jesus. Your blanket statement is like saying I cannot ask others for prayers on my behalf and I have no choice but to pray for that intention myself. That's a rather un-Christian concept.

The deuterocanonical books aren't new. They existed even before the New Testament began.

Unfortunately, you are taking verses out of context. Example:

Trust and only Trust to God. => Can I say....don't trust your parents then? If people ask you to pray for them, do you reply them that I can't because only Jesus can intercede for you, so go and fly kite and pray yourself? Think carefully before you pick and choose Scripture quotations, and taking things out of context.

Mary is even mentioned in the wedding of Cana to be the first to intervene to Jesus "they have no wine", and caused Jesus to perform His first public miracle even though He said "His hour is not yet come". Catholics are not just encouraged to ask for the saints' intercessions but to also imitate and model the saints' lives of faith, hope, and charity.

To seek the help of the friends of God to pray for us is a disgrace? Think again.

You may argue that praying to Mary and the saints is no different than asking someone here on earth to pray for us. Let us examine that claim. (1) The Apostle Paul asks other Christians to pray for him in Ephesians 6:19. Many Scriptures describe believers praying for one another (2 Corinthians 1:11; Ephesians 1:16; Philippians 1:19; 2 Timothy 1:3). The Bible nowhere mentions anyone asking for someone in heaven to pray for him. The Bible nowhere describes anyone in heaven praying for anyone on earth. (2) The Bible gives absolutely no indication that Mary or the saints can hear our prayers. Mary and the saints are not omniscient. Even glorified in heaven, they are still finite beings with limitations. How could they possibly hear the prayers of millions of people? Whenever the Bible mentions praying to or speaking with the dead, it is in the context of sorcery, witchcraft, necromancy, and divination—activities the Bible strongly condemns (Leviticus 20:27; Deuteronomy 18:10-13). In the one instance when a "saint" is spoken to, Samuel in 1 Samuel 28:7-19, Samuel is not exactly happy to be disturbed. It is clear that praying to Mary or the saints is completely different from asking someone here on earth to pray for us. One has a strong biblical basis; the other has no biblical basis whatsoever.

God does not answer prayers based on who is praying. God answers prayers based on whether they are asked according to His will (1 John 5:14-15). There is absolutely no basis or need to pray to anyone other than God alone. There is no basis for asking those who are in heaven to pray for us. Only God can hear our prayers. Only God can answer our prayers. No one in heaven has any greater access to God's throne than we do through prayer (Hebrews 4:16).

Sorry ifourtus,
The earlier query was in response to your second quote.
I think there also seems to be a misunderstanding as to what Catholics say or believe when they "pray" to the Saints and Mary.
A favourite prayer that is said is
"Hail Mary, full of grace,
the Lord is with thee;
blessed art thou amongst women,
and blessed is the fruit of thy womb, Jesus.
Holy Mary, Mother of God,
pray for us sinners,
now and at the hour of our death. Amen."
"Your earlier QUOTE

You may argue that praying to Mary and the saints is no different than asking someone here on earth to pray for us. Let us examine that claim. (1) The Apostle Paul asks other Christians to pray for him in Ephesians 6:19. Many Scriptures describe believers praying for one another (2 Corinthians 1:11; Ephesians 1:16; Philippians 1:19; 2 Timothy 1:3). The Bible nowhere mentions anyone asking for someone in heaven to pray for him. The Bible nowhere describes anyone in heaven praying for anyone on earth. (2) The Bible gives absolutely no indication that Mary or the saints can hear our prayers. Mary and the saints are not omniscient. Even glorified in heaven, they are still finite beings with limitations. How could they possibly hear the prayers of millions of people? Whenever the Bible mentions praying to or speaking with the dead, it is in the context of sorcery, witchcraft, necromancy, and divination—activities the Bible strongly condemns (Leviticus 20:27; Deuteronomy 18:10-13). In the one instance when a "saint" is spoken to, Samuel in 1 Samuel 28:7-19, Samuel is not exactly happy to be disturbed. It is clear that praying to Mary or the saints is completely different from asking someone here on earth to pray for us. One has a strong biblical basis; the other has no biblical basis whatsoever.

God does not answer prayers based on who is praying. God answers prayers based on whether they are asked according to His will (1 John 5:14-15). There is absolutely no basis or need to pray to anyone other than God alone. There is no basis for asking those who are in heaven to pray for us. Only God can hear our prayers. Only God can answer our prayers. No one in heaven has any greater access to God's throne than we do through prayer (Hebrews 4:16)."

And Catholics do not give the same kind of worship to Mary and the saints as that given to God.

Different levels of worship:
God=latria, sacrificial in character
Mary=hyperdulia
saints and angels=dulia

An analogy exists even in day to day life, you do not give the same kind of honour to the king or head of state as that to his subordinates. As someone told me rather interestingly, Catholicism has its order of hierarchy in heaven (and earth) just like a monarchy, while Protestantism is more like a republic.