I think that Jim Wallis is more of moderate than a liberal but "God's Politics" has some very good stuff in it. It kind of gets repetitious.
The point is mostly how the message about justice and poverty have
gotten forgotten in the current hullabaloo about gay marriage and abortion.
He has an interesting website:
www.sojo.net-- Sojourners. I get their newsletter but it is almost too much to read.
I really like "Stealing Jesus: How Fundamentalism Betrays Christianity" by Bruce Bawer. A few others some stuff by Spong is almost a requirement,
as is Matthew Fox. (These three are more about Christian liberalism, they do include stuff about general liberal concerns.)
I don't know if you have access but I like to listen to/ watch Democracy Now (this is on PBS and NPR some places and also Direct TV 375). This is serious liberal issue oriented stuff, not the stuff that was on Air America.
This is talking heads and the anchor has a terrible speaking voice, imo.
For more info,
www.democracynow.org
I also like NOW and Frontline on PBS, some NPR stuff, and BookTV on CSPAN2.
A couple books i have heard the authors but haven't read: Anything by Scott Ritter and a book with a title like Blackwater: the world's largest mercenary army (?).
--des