Finding a nice old vintage bicycle is not all that hard to do. Have a look at How To Find Vintage Bicycles, to learn a bit about how to find a bike for little or even no money. But before doing that, you should take the time to learn what characteristics are common to better bicycles. You can do this by spending some time browsing through Bicycle Quality.

I hope that is a bit of getting started help and good luck with your quest. By the way, welcome to the Bike Forums.