*under construction, but in the meantime: Here is a video of one of the people that has been the most influential in my own understanding of the New Testament and the gospel, N.T. Wright: http://www.youtube.com/watch?v=ICHovRHJAYY
Central to this page is going to be the 4 books at the beginning of your New Testaments, Matthew, Mark, Luke and John. They contain the answer to the question, “What is the gospel?” Read them! There is no substitute or more complete answer than you will find in those texts.