One thing that the four gospels certainly don't contain is first person testimony. If you look at them, you'll see that they don't even pretend to. (None of them are written in the form of first-person recollections.) They were composed (in many cases compiled) over a long period of time, collecting oral traditions and earlier texts in response to the needs of numerous early church sects. Even the names attached to their titles come from tradition, and not from any claim within the texts themselves.
Scholars (a reasonable consensus of them) consider Mark the earliest of the canonical gospels, and Matthew and Luke are very clearly rewritten and re-edited versions of Mark, containing big chunks of identical passages, which is precisely what we would not find if they were independently written testimonies. The authors of Matthew and Luke had theological reasons for making their additions and subtractions to the text. They were serving different early church communities, who all had different local traditions and theological preferences. The later gospel of John is radically different from these three, and contains a far more developed theology. There is plenty of internal evidence for all of this, and it's loads of fun to ferret out.
The early Christian communities were nothing if not diverse, with major sects favoring rival traditions, (Pauline vs. Petrine for instance) and the understanding of exactly who Jesus was (his Christology) was in constant dispute. Catholic orthodoxy emerged slowly from these communities, and ultimately succeeded in the marketplace. So, they got to establish the official canon, no doubt redacting the materials a bit in the process. (There's lots of internal evidence of this in the texts as well.) I don't begrudge them. I think they actually did pick out the best texts. (Have you read any of the gnostic and Nag Hamadi literature? I would have left it out too.)
New Testament criticism is one of my favorite topics/hobbies - I'm not a believer (though I once was), but I find the topic endlessly fascinating. There are lots of good books out there, based on scholarly research, and there's loads of crap in the more sensationalistic "Holy Blood Holy Grail" vein. I prefer to skip the speculative stuff.
Earlier in this thread, mousepod posted a link to "The God Who Wasn't There." One of my favorite scholars appears in that documentary - Robert M. Price. He's worth reading, and he has a regular Sunday podcast called The Bible Geek, in which he answers questions about the scriptures and the origins of the varioius faith traditions. He favors the view that Jesus himself is a legendary figure, but he gives all points of view a fair hearing, and his breadth of knowledge is stunning. Also, he's a very funny guy. You can find him at
www.robertmprice.mindvendor.com/
gosh, I was just going to post a sentence or two - oh well