So I have a problem.

Skyrim won't install on Steam.

I have had it installed before, in fact so far as I can tell it still IS installed, but steam thinks it is not.

If i look in /steamapps/skyrim all the right files are there, but when I try to run the game it says it needs to install the game. then it goes to a "Install - The Elder Scrolls V: Skyrim" window where it says it is creating cache file... forever.

As of right now I can't install, let alone play the DLC I recently paid for and am becoming more and more frustrated by this process.

Now what Bethesda?

Not a Beth issue, it's likely a Steam issue.

Try asking on the Steam forums.

I have never backed up my game files to the same partition. Also, when Steam Uninstalls a game, it leaves tons of stuff behind so you think the game is there.

Did you use the Restore program in Steam? Otherwise, it may not know there are files that you have backed up. If you try to launch from Steam, and it is not installed, then it will try to download the game again.