I've been using browser quick searches to do similar kinds of searches on free Amazon ebooks. It uses the ability of FF, Chrome, and others to use
%s syntax in bookmarks and/or search engine definitions.
Here's the URL pattern
Code:
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Ddigital-text&sort=price&field-keywords=%s
I use "fa" (for "free amazon") to denote this search, and use it like this in the url/address bar:
Code:
fa dogs
fa horror
fa graphics drivers
fa shakespeare
In firefox it's most commonly used in bookmarks. In Chrome you set it up under Settings | Manage Search engines | Add a new search engine.
Here's an example with pics showing how it works with FF.
B.N. In both browsers general quick searches can be configured by right clicking on the input field of most Search functionss, but more specific searches like the one above are easier done by setting it up manually.