I been really in this simulator since its first release. Now the second version is out and has never been funner.
You can download the full public alpha and play it as a demo. If you want the full game you can make an online purchase and unlock it.
www.liveforspeed.net/
This is by far my favourite simulator. You will need a wheel for best gameplay. If not use the mouse (the kb is useless).

That looks prettttty.. but I cant find sys requirements. I also just recently DL'd trackmania sunrise. Hey, you should all go get it and we can netplay together, LOL.
Ren