If you have played the original game, you will know where to look for secrets.
Download from the Workshop:
Workshop (It is also compatible with Gmod)
Here is a video from an earlier version (thanks to Robotortoise):
Ocarina plugin for OoT3D_Hyrule
In order to use this sourcemod plugin, put the ocarina.smx into "tf/addons/sourcemod/plugins" on your server.
Ingame, type "/ocarina" to open the song menu. Choosing a song will teleport you to the equivalent pedestral.
Thanks to Jim for this useful plugin.
Ocarina of Time 3D playermodels (Updated 05-15-15)
Majora's Mask 3D playermodels (Updated 03-28-15)
I've created a bunch of playermodels. Those models are rigged to different TF2 skeletons. Useful, if you want to roleplay or populate Hyrule with various Zelda characters.
They are intended for the Model Manager plugin.
And here are the entries for the cfg file: Paste.bin