I recently found ALL the cards on eBay, a complete set which is now IN MY COLLECTION and that I have scanned and uploaded for your viewing pleasure. Enjoy!
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COUNTDOWN: This set goes from card #1 to #29 and features a brief retelling of the events in Kingdom Come on the back of the cards.
CROSSROADS: From card #30 to #50, the cards showcase the most important players in the KC Universe with brief explanations on the back, a kind of who's who.
SKETCHBOARD: These cards contain, as the name implies, sketches on 15 characters from the series. I have scanned both sides of the cards because they contain interesting info on the characters by the creators, Alex's comments are in black and Mark Waid's are in red.

CREATOR COLLECTION: This is the jackpot of this trading cards series. All the other cards, although they're cool, they are reprints of previously released art, while these contain NEW art. So, if you're not an insane collector like myself, you'll only need to get these 6 and you're set, the problem is that they're very difficult to track down. Hey, I bought the entire set to get them.
CLASSICS: These 3 cards pay tribute to 3 classic covers from the Golden Age, each represents Superman, Batman and Wonder Woman.

UNFOLDED: These cards reprint the character-filled covers of issues 1, 2 and 3 of Kingdom Come in 3 fold-out cards that sport a character guide on the back.
Of course there's the obligatory checklist card and next to it there's a promo card which was included in Wizard magazine. This promo card has the same art as card #20 on the flip side.