The History channel is launching a new program called "Scammed". While not specifically relating to narcs, the basic premise is the same and frequently Lonely Hearts are targeted to be scammed of the money and other properties by Con Artists. Narcs are frequently con-artists.
I loved one line in the program I thought well worth keeping mind - "If you think you are too smart to be scammed - (the con-artist, I want to meet you!". I'm already starting to learn a lot, I've had an interest in this for years, so far, much is familiar. I think the show is worth catching if you can.