Advanced Search Form for Magento

I require an advanced search form to be added to the sidebar of my store. It needs to include 3 drop-down select boxes, each populated with the values of 3 different attribute sets. It does not need to include a keyword input field. If possible, I would like the second and third drop-down values to be refined using ajax, based on the user's selection in the first drop-down. If the search results can then be filtered like the basic search form - this would be my preference. This feature is urgent and needs to be completed within the next 24 hours.