where can i download windows xp ?

ok i hope you guys can help me with this, so i got this computer that its missing the hardrive so i but a new hardrive on but im not exited with ubuntu as its just too much just to be able to play a videogame , so i want to put windows xp on it but it i dont have the disks but i have the product key , where can i download xp .iso , with minimal and the list risk posible.

any torrent site, the risk factor is always there and even if you have a product key, you will probably need a patch anyways... now if i could just remember where i got my patch...

tell you what, on wednesday ill upload to rapidshare and give you link.