how does a NTSC tv tuner work surrounded by a laptop?

Answer:

Either an antenna or cable, probably you could even hook up a satellite using a coaxil cable.
what brand and model? I have both Toshiba and HP Media center Edition. Toshiba TV Tuner had a cable connector converted to 3.5mm mini plug that plugged into tuner module that fit into mobile slot. HP had an external module that standard cable connector directly and plugged into laptop via USB cable. You should look for something similar, or find the dongle/converter from the mfg or on Ebay