A few months ago, I wrote a book, The Right Opinion: A Heretic's Voice from the Ivory Tower which looks at the leftward leaning tilt of academia.
As a follow-up, I wanted to alert you to two great articles in the Washington Post which take up this debate.
The first article by Robert Maranto (who was a Clinton appointee)argues, ala Goldberg's thesis in Bias, that academia is accidentally homogeneous, but there are subtle ways to push conservatives out of the field. It's a great read and I won't summarize it all here.
Then, there is a response to Prof. Maranto's essay by his mentor at the University of Maryland. He basically argues that conservatives won't go into academia because they value money too much. As a conservative academic who makes less than $45,000 a year, I obviously disagree with his thesis. I would also point out that in my 10 plus years in academia, I have ONLY heard academics complain about their pay.
Either way, I hope you find time to read both articles. They are a little long, so it may take the not-to-bright folks over at EFFin Unsound about a week to understand them, but it's worth the time.