If you have a cable box you just need an rgb to vga cable and it should plug right in to both. If you don't have a cable box then mrbiggums is correct you will need to install a tuner card into your pc.
"If you want to be Elite you have to do a righteous hack"
CPU: Q6600 (G0) @ 3.1 stock voltages
RAM: 2 gig Crucial ballistix ddr2 800
PSU: pcp&c 750
Mobo: Abit IP35 pro off limits
GPU: MSI NX8800GT 512M OC
HD: 250gb Barracuda x2 (Raid 0) 80gb Barracuda x4 (JBOD)
3DMark06: 14693