Inside Higher Education has a column with the absolutely standard advice about what to do and how to move on. As far as I can see, it shouldn’t surprise you unless you are a complete novice. Still, as I remember, after a failed interview one’s beliefs are pretty jumbled, and the article should help you get back to reality.
Hyperlinks aren’t working for me right now, but the article is here: http://www.insidehighered.com/advice/2011/01/19/kelly
Do look at the comments, some of which are very apt. E.g., inside candidates who are long term adjuncts are going to have a very hard time.