These are just some more modern racing games that run on intel based Macs that utilize steering wheel support. There are others that I have not listed.
1. Dirt 2
2. Auto Sport Driving (I am the developer of this game so I really like this one!

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4. Virtual Grand Prix 3
5. Toca Race Driver 3 (older)
6. Colin McRae Rally Mac (older)
7. Ford Racing 2 (older)
8. Redline Racing (older)
As far as wheels go... One of my favorite subjects! I am the developer of the Mac App Store game,
Auto Sport Driving and I have tested quite a few wheels in OSX Snow Leopard and Lion. These are the findings of my testing. All money is listed in US Dollars.
Here is a list of the wheels and the results on the Mac side that I have tested.
VERY IMPORTANT: Force Feedback has been left out of Lion for some reason. You will have to re-install the kext to get the Logitech wheels to use Force Feedback.
I have instructions on how to do this on my site HERE.
Wheels WITH FORCE FEEDBACK (must install FFB kext if using 10.7)
1.
Logitech Momo racing wheel (black) - Works perfectly! All the buttons on the wheel along with the sequential shifter are beautiful. But this the lower end wheel model from Logitech and does not have the best FFB. But FFB does work well. If using Lion, you must install the Logitech FFB kext to get FFB to work. These are now discontinued , but you can find them on ebay for anywhere from $50-$100.
2.
Logitech Driving Force GT - This wheel works very well also but not all the buttons work on the wheel. For the price, this wheel is great. It does have 900 degrees of rotation if you like to drive that way, but it does not always work right in OSX and can be buggy. It is better to plug the wheel in after the Mac has started. This should disable the 900 degrees of rotation and makes for a better driving and FFB experience. This is a great wheel. They are sold in a lot of stores and online for $130-$150.
3.
Logitech G27 - My favorite wheel for the Mac! Again, it is better to plug the wheel in after the Mac has started for a better racing experience. The FFB is so much better and the wheel itself is beautiful. It is the best unit for Mac in my opinion, but it is a bit more expensive at anywhere from $230-$299. But if you have the money, this is the wheel to get.
Note: The G25 is also out of production, but works very well on the Mac. All the same steps should be taken as I have listed for the G27 as it is the successor to the G25.
Wheels with NO FORCE FEEDBACK
1.
Thrustmaster F430 - Works very well and is a beautiful wheel that can be purchased fairly inexpensively if you shop around. But again NO FFB!
2.
Thrustmaster Ferrari GT Experience wheel - An inexpensive wheel that works well, but is not as flashy as some other wheels. A lot of plastic and it feels a bit cheap. NO FFB!
3.
Thrustmaster T500 RS Wheel - Simply one of the best wheels available right now. But with no FFB, it is not really a great Mac alternative. This wheel looks about as good as any wheel out there and is made to last. The pedals are great and the wheel itself feels like a real wheel. I really wish someday we can get FFB on this wheel. But this wheel is expensive! Around $600 and NO FFB!
Again, I have not tried any of the Fanatec wheels, so I am not sure how well they work on Mac. These are MY findings and the racing games I have tried on my setups. If you purchase a wheel and have results, please let me know if possible.
As a side note, Real Racing 2 is a great game, but DOES NOT utilize steering wheels. You can use you iOS device to steer, but not an actual steering wheel.