The only ones I really really liked were the NFS games, other than that I don't really enjoy racing games on the iPod. Oh and the recent Crash Bandicoot game is good as well. My favorite racing games are on the PSP/PS3 though.
This will never happen if you know the history of Australian game development. But I understand the irony Maybe Jet Car Stunts 2 will show the next stage on But there again that will be hardcore gaming...