How do i exit stony creek cave?
Im at a waterfall but no way out.

Do you see the dead Breton hung over the wooden beam there? It's a very linear cave. You go out the way you came in. You went in there to get Finn's Lute, right?

http://images.uesp.net/4/47/SR-interior-Stony_Creek_Cave.jpg

Also, next time I suggest google or http://www.uesp.net/wiki/Skyrim:Stony_Creek_Cave

no i went in to get dwemer schematics for an enhanced dwarven crossbow and im at the end of the cave with a waterfall and the quest marker is up above the waterfall in what appears to be a room.

I think you need to enter from the other end - one of those Dwemer ruins further up the mountain. You then exit that ruin into the cave.

The quest marker is misleading for this quest. You actually need to find and enter Kagrenzel to get the Dwemer schematics. You will exit Kagrenzel at the Stony Creek waterfall.

thanks for all the help.