So lets say I have a picture... I adjusted it, cropped it, rotated it.. whatever. THat's my new version and maybe I posted it some places too.

What about down the road if I want to go back and use the image for something else? Or maybe I want to apply some different techniques to it? Is there anyway I can "start from scratch" I have a mix of RAW and JPGs (newer are RAW) if that matters...

Hopefully I'm just missing something and this is an obvious thing

Create a virtual copy, and use that. You can go back to the start - Reset - or work on from where you are now.