1: Don't. A game that isn't worth paying for is a game that isn't worth playing.
#2: But you will try anyway. I still can't tell you how to find torrents on a public forum like this aside from sending you somewhere loud and proud like thepiratebay.com.
If you do find a torrent, there's web tools like bitlet that'll let you download it like a regular file,
http://www.bitlet.org/
Your best bet is making a friend that owns the game who will let you borrow the disc, or a friend online that can send you the disc image directly. Or just buy the game and rip the image onto your hard disc.
What I CAN do is tell you that, once you have a disc image, you'll need a virtual drive. Those are perfectly legal, and a lot of gamers use them because they read faster than CDs and free up your physical drive. Here's my favorite,
http://www.slysoft.com/en/virtual-clonedrive.html