Need Help with the TV!

[gr0undzer0]

Just letting you guys know, I am the typical male that never asks for directions/help. I have tried to find useful material on setting this up, but have been unsuccessful thus far. I will do my best to describe my current setup and what I am trying to accomplish.

What I built:

2.6 GHZ Core 2 Duo Processor
2 GB RAM
GeForce 8700 (HDCP ready)
AverMedia AVerTV Combo PCI-E tuner card
HTO Striker 7.1 Sound Card

What I Want to Do:

I built this HTPC with my current setup in mind. I have a 46" Samsung Plasma (about 2 y/o) with a 7.1 surround sound system. I currently have all of my components routed through my stereo system, using component cable (G,B,R) and S/PDIF. My idea was to build this machine to allow for playing HD, 1080p .MKV videos (which works wonderfully) and bypass the need for an expensive blu-ray player. I also would like to route my TV through the media center, which would greatly help my wife with using our system (right now she is clueless).

My Problem:

I have looked online for an answer but cannot find one. I tried to run my coax cable directly to my tuner card, thinking that it would pick up the signal and be able to go from there. However, when I scan for the channels all I get is static. If someone could guide me in the correct direction, I would be extremely grateful.

John