As you played your games on ENT they have a list of replays you can download if you go to this LINK.
If you wish to save future replays go to Options=>Gameplay=>Enable "Automatically Save Replays" This will be saved in User/Documents/Warcraft III/Replay/Autosaved/Multiplayer/ as of patch 1.28 If you're working with 1.27 patch still it is in the Program Files(x86)/Warcraft III/Replay/AutoSaved/Multiplayer/
Do note, if you're hoping to review your old replays you will need a 1.27b patched client. If you are already 1.28, you will need to downgrade by doing the following. 1. Uninstall WC3 2. Download installer from Battle.net website (or use CDs if available) 3. Download the offline 1.27b patch HERE 4. Install the downloaded patch 5. Launch client
If you want to have the ability to review your replays and play with the new patch, copy your 1.27b installation folder to a unique location, and update your main client to the current 1.28 patch.