if you are thinking of getting the CD version it should already come ready patched so there is no need for anything else,i got mine from here...
http://www.play.com/Games/PC/4-/1360...&ob=Price&fb=0
as you can see just below the main pic i only paid £6.61...
now its gone down in price so you getting it cheaper
its genuine and i have had no probs with it,my cpu is just a little under the recommended requirements so i do get some framerate drop in a couple of areas but apart from that its fine,as for game play you can adjust pretty much most of the settings to make it ideal for your style of play,i use a hand held controller at the moment but i understand that a steering wheel is far better most people say the logitech g25 or g27 but they are not cheap which is why i dont have one yet....
i really love this game and despite its few minor (imo) flaws i play it all the time and i hope they do bring out some changes to improve certain aspects of it,all i can say is happy driving....