if you want to connect a new "led lcd tv" to your computer then you will want a video card with an output port of DVI or HDMI. if you don't know what the ports look like search google for a picture.
if your video card doesn't have these two outputs, or if you have integrated video....post what connectors you do have. if you don't know the names look in your manual.
if you have a dvi port there is a cable that goes from DVI (male) to HDMI (male) which you will use to connect with.
if you have an hdmi port the typical HDMI (male) to HDMI (male) cable is the one to use.