The only one I really like is Barnes and Noble, even though it is a lefty outfit. They can’t control all the content, and they do sell conservative authors, although it pains them. I love it when I plop a Coulter, Levin or Steyn book at the checkout.... lol
I was a big fan of B and N’s main competitor (Borders). I used to love to dig through the bargain bin and walk away with two sacks full of books for less than $50.