I don't think you can get a TV Tuner that cheap. I think I paid 200 or 250 for mine from Elgato. Quality isnt the best but that might be because the computer I use it on is underpowered. I hear the Eyetv EZ is supposed to have slightly better quality though and its supposed to be cheaper ($149).
I have seen the Miglia TV micro from the apple website for $99. Read great reviews on it. Im planning to buy one also for my MBP so I could cancel my tivo subscription.