I have the Matrox Marvel G400-TV, which is an old 3D/video capture combo card in similar vein to the ATI Radeon series, but Matrox's video capture capabilities have always blown the Radeons out of the water. The Marvel only had 3D power comparable to a TNT2/Voodoo3, but it's video capabilities are still amazing, which is why i still use it (if you can watch a movie in Windows Media Player, you can watch it full screen on TV). It cost me $250 several years ago, has RCA & S-Video inputs and outputs, and one TV coax input, captures at 704x480 rez.
For stand-alone capture cards, Miro (Pinnacle) capture cards have been quality picks. No TV coax connections, but of course has RCA & S-video ins and outs. Captures using proprietary MJPEG format codec, at 640x480 rez. If you can find it, a low-price model would be the Miro DC10; for more expensive models, try Miro DC30, DC30+, DC50.
If you prefer to play around with DV formatted video instead of MJPEG (and spend more money), you could try out analog-to-DV hardware. Devices from Canopus and Dazzle are good picks, though Dazzle often requires you to already have firewire ports on your comp to receive the video data coming from the capture unit (some are external units, some are internal and fit in your drive bay).
The Dazzle Hollywood DV bridge is quite expensive, and requires pre-existing firewire ports. The Canopus units aren't as expensive, and come with their own firewire add-in cards.