OK, here is my updated list....please let me know if I missed one or the casino no longer has Win Cards:

Excalibur
Casuarina
Circus Circus
Four Queens
Hard Rock
Luxor
Mandalay Bay - ?????
Tuscany Suites & Casino
Cannery Casino-Hotel
Tropicana Resort and Casino - New
Avi Resort & Casino (Laughlin)
Buffalo Bill's Resort & Casino (can only get once in lifetime)
Whiskey Pete's (can only get once in lifetime)

That should be all of them unless they have stopped the promotion.