I use the Fusion 3 Gold card from DVico but they have newer cards now like the Fusion 5:
http://www.digitalconnection.com/produc ... ion5rt.asp
Then, I use a $ 50 antenna from RadioShack:
http://www.radioshack.com/product/index ... age=search
Now, you can use any antenna but that's the one that worked best for me. Also, you could use your cable (like from Comcast, Cablevision etc...) if they have unencrypted locals. You won't know that till you try. Satellite won't work since it's always encrypted.
The only HD channels you can record, since they're the only ones unencrypted, is: ABC, CBS, NBC, Fox, CW, MyNetworkTV, Telefutura, PBS, and Univision.
It's well worth the purchase. Just make sure you have a fast PC, lot's of RAM and a big hard drive w/ lotsa free space.
Any questions just let me know.