Bob,
First off, thanks for your response, and I'm sorry, I meant an HDMI input.
The Blackmagic Decklink HD Extreme 2 that I have has HDMI inputs apparently (Model#BDLKHDEXT2). I actually just bought this converter...
http://cgi.ebay.com/VGA-Audio-HDMI-HDTV-Converter-Adapter-Laptop-PC-/220743...
...which I hope it works :S
Any other suggestions?