I actually have an Amazon advertisers account set up already, but have been holding off putting more ads on the site. There are a number of ways to do it. I can set up targetted links so if a person clicks through and purchases a book we get a few cent, or general context-sensitive ads. The former would be great for a book reviews section, as it provides an excuse to put a link to where to get the book. The latter is general, so will atke the form of a banner or block, and I'm undecided on where that should go. I don't like lots of ads on sites, so I'm careful about what we do.