What antenna do you recommend?

I'm getting rid of my $200 cable bill! I've got HuluPlus and Netflix streamed to my PS3 and I've purchased a Tivo (should be here soon!). My issue is the broadcast stations. I get CBS, Fox, NBC, PBS and some other local "jewels" but I'm missing ABC. I e-mailed the local affiliate and they told me obviously my antenna was inferior and suggested a $100 antenna. Is this necessary? I've looked up my location on the FCC website (down to my address) and they say that the signal is strong. Any suggestions?