Wikipedia has an article on valid but illicit, who knew?
As a matter of fact Wikipedia has quite an extensive collection of articles on the Catholic Church and Christianity. I find that the articles are generally quite good, sometimes even better than the Catholic Encyclopedia. They often include information on the beliefs of other Christian churches and honestly compare the beliefs of various groups, without taking sides. By this I mean they also do not take a secular stand either. I find it a good resource, when properly balanced with other sources.
I find the 'net in it's entirety an amazing resource for an aspiring apologist or catechist.
I've written on the positive effect the Internet can have by exposing groups or individuals who are supporting non-dogmatic stances or performing illicit practices.
Because the Vatican posts just about everything it is a great way to read documents propagated by the Holy See. The Catholic blogosphere passes on news faster than CNN. There are literally hundreds of useful apologetic and catechism sites, which with a little cross checking can ensure that what you teach is the real deal: the Truth as revealed by Mother Church.
It is a much better way to spend your time than "must-see" TV.