What vote-counting mechanisms do counties use?

A request from our comments boxes:

Has anybody put together a county-level database showing which vote-counting mechanisms counties use nationwide? I've collected a bunch of county-level electoral and Census data for another project. I'd be interested in seeing if there's any relationship between the type of voting machine a county uses and its electoral results, net of other county characteristics.

Send me a note at tdomina(at)gc(dot)cuny(dot)edu if you can help.

This shouldn't dissuade the approach that looks at the numbers precinct by precinct, but it would certainly be interesting if optical scan or touchscreen counties had stronger Bush turnout than demographically similar counties using traditional, punch-card methods.