Horse racing games are popular in some countries, but not the US. Because of this, you may want to consider importing Derby Time 2006. In the game you raise and care for a horse and then have it compete against other racers and horses. Derby Time 2006 also supports infrastructure mode to allow you to race against a friend's horse. Last year's Derby Time got a 7/10 from Famitsu, so it sounds like it's a decent title for horse racing fans assuming you know Japanese or are adventurous.