New Advent :  this site gives you none stop access to not only to the Catholic Encyclopedia but....an endless listing of the Early Church Father's writings.  A must have for any Catholic Apologist.

Two Thousand Years of Catholic Writings: Another site devoted to the Writings of the Church Fathers.

The Council of Trent : Trent....what is Trent? Well.....check it out....what exactly the Church dogmatically taught at this Great Council of the Church.  

The Second Vatican Ecumenical Council :  Ah....Vatican II.  Probably the most misunderstood council of the Church.  Find out what VII really said....right here :)

Keeping Catholics Catholic Page XXV-Timeline of the RC Church:  Gee...do you want to know what happened in the year 313 ad?  You can with this awesome Timeline of the Church...going from the beginning to the present.