Well...as a high school Latin teacher, I might have a little expertise in the field. The first thing you need to identify is what you want to read. That dictates what you need to focus on. It sounds like you are most interested in the early Christian writers, so my suggestion would be to start with the Vulgate (which is the Latin translation of the bible done by Jerome). The Latin in it is fairly simple, but more importantly, it is something you most likely already know. That will allow you to have an easier time with the vocabulary and the forms.
Here is a link to a decent site with the Vulgate and the King James Version side by side. http://www.latinvulgate.com/