From ENT Wiki
Download Warcraft 3
If you have lost your CDs, you can download Warcraft III and its extension The Frozen Throne directly from Blizzard's website, and play the game.
- Log into your account. If you do not currently have a Blizzard account, you may create a free one here.
- Now that you are logged in, go to the toolbar, click on "Games and Codes" and then "Code Redemption".
- Enter your Warcraft III CD-Key into the bar. Once this is done, click on redeem code, and then you should see the game you have just redeemed. Click on continue.
- Repeat the action with the Frozen Throne CD-Key.
- Once this is done, return to download client, scroll down to Classic Games, and you should see Warcraft III and The Frozen Thrones as download options.
- Select either Windows or Mac and your download will start.
- Note: You will be asked to select a directory for the download. The default directory for Warcraft III is the following: C:\Program Files (x86)\