There are no good modern racing games outside of one or two titles on the Wii.
Step 1: Buy an N64 on eBay
Step 2: Get Diddy Kong Racing, Beetle Adventure Racing, Star Wars Episode 1 Racer, San Fransisco Rush, Extreme-G 2, F-Zero X, Waverace 64, and Lego Racers.
Step 3: Enjoy the next two years, a lot of these games are really terribly hard but they're all fun as hell. Which is more than I can say for most current-gen racing games that are only moderately difficult and not fun at all.