Instructions
Look in stores. You may find some reissued vintage board games in toy stores or even Target or Wal-Mart. They often have them around Christmas time. Although computer games are more the rage, there is still an appeal for board games.
Stop at yard sales to find vintage board games--especially if it is a young couple trying to get rid of their parent's stuff. Board games were extremely popular in the '50s, '60s and '70s, so keep an eye out for those yard sales.
Try flea markets. They are notorious for selling things that used to be the rage. You need to scan the booths and check out the nooks and crannies to find what you are looking for. Double check and make sure all the pieces are included.
Check out eBay for vintage board games. There are other online sites as well listed in the Resource section to get you started.
Check out the games before you buy them from any source. You don't want to buy a game that has irreplaceable pieces missing.