im sure at www.ebuyer.co.uk they have some cheap ones (that is if you live in the UK because on your profile it says I will never find this place, it doesn't exist. lol)
I have a TV tuner card (see below)....it's pretty good. I get a good, clear picture, and the software that comes with it is pretty good as well. I've never had any problems with it, in fact, I'm watching right now. I bought it on ebay for ~$150.