There was originally a bug in which purchased cards merely went into the players miscellaneous inventory instead of being entered into the deck. Note that these don’t really change much other than the look of your deck. Each of the main casinos has a deck of cards available. You can buy new cards from many different merchants in the game. You should get a full set of cards all on your own after you are introduced to the game by Ringo in Goodsprings. Normal gambling in the Casinos will also allow you to make money.

Note that if you really don’t like it, you don’t have to play it. To start with, note that PC players have to play the entire game with their keyboard (this seems to cause a lot of confusion).

Caravan is a great way to make some easy caps in Fallout: New Vegas, but it’s a slightly complicated game for new players.