I've finally started working on v2 of my Compendium Search tool. The next version will include the ability to do filtered searches. If I have time, I will also add multiple sorting columns to the list view for things like level, class, etc.
Here's a teaser screenshot of the new interface. When it's done, each tab will have controls for filtering the search:
In the meantime, Compendium Search now has a site on Google Code:
You can download the binary and browse the code if you're interested in using the web service API for your own project.