An idea for development

I’m wondering if there is any really LEAN database plugin for WordPress. In short, I would like the “general public” to be able to access it (like a “poll” for example), and plug in about 10 pieces of information. (Data entry, in short.) All the info goes into a file on that item, and more can be entered.

Then we need a way to sort the accumulated data from about 4 of the 10 fields (such as “county” of a state, where we can get that list of all those entered from that location). That’s it — down & dirty index cards basically that we could pluck from according to very generic criteria. Do any such plug ins exist?

Thanks!