Just to throw some devil's advocate dust in the air...I'm a big fan of using alternatives to Amazon and other oversized nodes on the network - actually I'm a booster of brick and mortar - but I'm not willing to bar the commercial space from public space just as a matter of principle. After all, Alibris and Powell's sell through Amazon, too. It's dominance and stifling the alternative that I object to. I'd rather Amazon than B&N ;-)
A couple of cool booksellers in my neighborhood:
Monkeywrench books - a radical collective bookstore in North Austin.
Bookpeople - the big indie bookstore in Austin. Center of the "Keep Austin Weird" universe.
RC McCloud also writes at The Safe Word