Here is a collection of links to the bible.org Introduction/Argument/Outline articles. These are written by Daniel Wallace and are great introductions to each of the New Testament books. Inside each link you will find discussions of authorship, dating, audience, setting, a brief summary of the book, and a detailed outline and more. While not intended to be exhaustive, these articles provide a solid introduction to the issues related to authorship, date, and possible textual problems.
My hope is to add links in the future that augment these introductory articles. Stay tuned.