Finding drawings (prize) to enter

Suppose for example that I want to try to win a new Porsche. There are lots of contests where all you have to do is enter your name for a chance to win. What’s the best way to find contests offering a specific prize?

I was going to say I’ll enter any contest that just wants my name even it it’s not for a Porsche, but the Google ads appear to be telling me that http://www.freecontests.ca/ and http://www.scapromotions.com/index.php are the places to be. That last one looks like you might be able to search that specifically.