I basically look every where. Although, admittingly I have never tried a garage sale or flea market. I have had some luck on Teletrade in the past but it seems like that is getting harder and harder. Some of the "seized property" auctions appear to be worthwhile.
It was my wifes and she finally let me open it. I asked her for years! There were some Morgans also. The best e were the Kennedys. There were 18 of them and they all were mint state were 1964s
Of course I owe her big time now, but its worth it.