I second what sws says, except narrow your year search to 2008-2010 and any distance from your location. 2010 was last model year for the Sport Trac, and the Adrenalin package was available only 2008-2010. If you're really serious about getting one of these you may have to travel to get it, or buy it and have it trucked to you. BTW, I found my 08 in a CarMax ad on AutoTrader. It cost me $140 to hold it and have it trucked from CarMax's Oklahoma City store to Fort Worth for me to view. As soon as I saw it, it was a done deal. Love my STA.
I used Autotrader, best site to narrow your search using criteria including engine and drive, still only found 6 tracs in the whole US that fit what I wanted, had a dealer trailer it up from PA to CT.
Just did a search on cars.com: 2008-2010 Adrenalin, any distance from my location. Got 8 matches - threw out two because they weren't STAs. Left were 2008 (2), 2009 (1), 2010 (3), all at dealerships. Price range $20,477-$27,995.