Here are a few great websites if you are interested in reading some of the primary sources from the time of the early Church. The Early Church Texts website is an incredible resource with almost anything you could possibly want in regards to early Church history. It is organized and searchable by people, places and events. The only downside is that this website is fee based, but it is well worth the few bucks. There is also a link to the New Advent encyclopedia page for the early Fathers and texts. You really can't go wrong with the New Advent Encyclopedia. It is definitely biased toward the Roman Catholic position, but it is all and all fairly balanced in its approach.