what do i need to be able to wath tv on my monitor?
an external or internal tv tuner card.there are options for hdtv tuner also from ati.if you want to record tv shows as well to your hdd you might want to consider a pvr card.a hauppauge pvr 150 should do you well for about 70$ but thats only if you want to record tv shows.ati hdtv wonder for hdtv for about 160$ and up.
well, money isnt the biggest problem. i want good picture quality (and recording sounds actually quite useful).
what would i be looking for more precisely, and where can i get one?
hauppauge deifinetly, but if want dual tuners so that u can record 1 show and watch another or just record 2 at the same time then ull have to go for the hauppauge mce500