I just got a second computer. I wish to download WoW and the Burning Crusade off the website. All I see is 10 day trials. I dont have the original disk.
Any idea where on WoW website I can download?

If you have your computers networked you can just copy the WoW folder from one to the other. I've done that a few times.

Also,

There is no difference between the "trial" download and the purchased version, the only difference is your account. Instead of logging in with the trial account info they give you, you just put in your account info and you'll be good to go.

http://www.worldofwarcraft.com/downloads/wowclient-download.html

Blizzard introduces a TBC 10 day Trial. Makes you wonder how many accounts there are without the expansion upgrade...