I've downloaded a couple of mods and they give the exact path into the Steam folder to unzip. These have worked perfectly.

Tonight I tried to download the enchanting table for the Whiterun house and here's all it says:
Install:
Unzip into Data folder, activate plugin within your launcher.

I tried putting into the same folder as my previous downloads but it didn't appear in the Data screen when I relogged into the game. I can't find a data file in my Steam file nor in my Skyrim folder. Any idea where this folder is?

I did use default paths for the game install.

If you know the name of the file run a search and then open the directory where that file is located. Move or copy the file(s) as needed.

C:/Program Files(X86)/steam/steamapps/common/skyrim/data


On windows 7, at least. Should be similar on other stuff. I made a bookmark for it.