I just bought a new hdtv, do I have to get one of those set top boxes from the cable company to make it work? I'm already paying $9,99 a month for 2 boxes and this TV I would like to just put in my bedroom and not pay more.
If your cable system still has Clear QAM channels you can just hook it up to the cable, set the input to cable, and scan for channels. You will be limited to the "limited basic" channels. If you want "extended basic" and above channels you will need a cable box.
The other option is to use an antenna for your new TV. Depending on your location, you may be able to get more channels than your cable company offers in Clear QAM, and in almost every case the picture quality will be better. Of course, reception is entirely location dependant. The best tool for finding out what channels are available (for free) in your area is TV Fool. Another useful site is RabbitEars.Info.