Many of us use price:[0 TO 0] to find free books. Unfortunately that search is currently also returning unavailable books (i.e. books without a price), which is disturbing the search results. The individual volumes of the CS Lewis collection are particularly an issue, but they're not the only ones.
This is made worse by the fact that these unavailable books are marked as "Live", so they can't even be excluded that way.
It would be a big help if unavailable books either (a) didn't show up with a zero price, or (b) didn't show up as Live.
<edit>I'm not the first person to request this.</edit>