This set-up looks pretty nice, but it’s a bit pricey:
Here are some other top of the line controllers:
http://www.thomas-superwheel.com/
http://ourworld.compuserve.com/homepages/extreme/
http://www.actlab.com/index2.htm
You know, I picked up GPL a long time ago, but it is impossible to play with just the keyboard. I couldn’t decide which controller to get, and never got around to picking one. Maybe it’s time for me to bite the bullet and get one…
Eric
The only wheel I have is a little controller from InterAct. Its called the “UltraRacer PC.” Its a mini-wheel not unlike a remote control car controller. I find it extremely precise and compatible with ever game I have (sets up as a 2 axis 4 button stick). After using it I will never go back to a full size wheel, I like it that much. Its also very comfortable to use… you could literally use it for hours and not get tired with it.
The best part is, they’re damn cheap! The only thing though is that they might be a little hard to find nowadays. Interact doesn’t even appear to have them on their website anymore.
http://www.joy-stick.net/reviews/wheels/uracer.htm
http://www.avault.com/hardware/getreview.asp?review=ultraracerpc&page=1
I’ve always just used a plain old CH Flightstick joystick for driving games. I tried a force feedback wheel for a while, but couldn’t get used to it, and going off the road with Colin McRae Rally 2 nearly shook the desk apart! I think sticks also work better for bike games, using a wheel to lean over a bike is too strange.
I have lots of racing games, but I’ve never tried a wheel. I love my Saitek P750 joystick/pad. The design is nearly an exact copy of a Playstation controller, plus the joystick has an option where it can be used for just x, just y, or both x & y. This setup is great for racing games; one button for accelerate, one for brake, one for handbrake, and the joystick for steering.
The great thing about the little controller I mentioned is that the throttle/brake are also analog. They are off a little “handle” you control with your index finger. In GPL, if you just have a “button” that you press, I gather your throttle is either fully open or closed, or brakes fully applied or not. Both would be pretty much suicide in this game as I think your car would be uncontrollable. I just can’t see how digital controls for the throttle (and even brake) would be playable in this sim.
Forgot to mention that the P750 also has an analog “wheel” in a position where it can be operated by thumb. Sounds similar to what bernse is describing.
Anyone up to giving this a half a try over the net?
Don’t expect me to be any good, but I wouldn’t mind seeing how it plays.
Coldfire?
Dude, I just got it up and running yesterday!! So far, I’ve only trained at the ‘Ring a few times. The BRM is a LOT easier to steer than the Ferrari, but man, I still spin off 25 times per friggin’ lap! 
I’ll be on holiday next week. After that, I promise to buy a decent force feedback wheel and get all the necessary pacthes to play online. I’ll be the guy with the orange helmet that crashes into hedges all the time. 