I'm trying to understand the whole situation, but it's hard with huge controversies like this. I'm interested in any reliable articles on the topic as well as differing opinions on it. Thanks!
I did a report on this last year. check it:
Brown University resource page on Iran-Contra
I also looked at the chapter on it in The Untold History of the United States by Oliver Stone but people have a lot of opinions on him.
If you want to get into the more "conspiracy" side of things, The Dark Alliance series by Gary Webb is good because it gets you started on the connections between Norwin Menses and Danilo Blandon with contras in South America.
Hope this helps!