So there's this guy named "AFM" that measures the rolling resistance of tires and posts his results to Biketechreview.com and other bike forums.
I took his list and made an eBay search tool out of it, so you can search for these quick tires on eBay.
Link to spreadsheet: Google Spreadsheet
Fastest road clincher tires: http://tinyurl.com/3oezmky
Fastest road tubular tires: http://tinyurl.com/3dwxg6x