What's it for?
What can I do with it?

I've done some research and someone said you can pay a guy to repair it for you, if so who and where is he?

I think they are just a bit of flavour, like the pots and pans and stuff.

And why would you need to as this game is full of soul gems? But i also wondered what they were for. I don't bother picking up the fragments

I'm getting enchanting really high, and now that I want them, they seem to be in short supply

Totally worthless, they are. Just a misc item to make the game seem to have more content, well they make a good vendor-food.

Dwemer ruins. Seriously... more than you could possibly use or need. I had like 14 Grand, 30 petty and who knows what in between them when I came out after doing two of them... where there were Dwemer there are machines powered by the gems.

hope that helps... my enchanting was the first thing maxed as a result. My blasted alchemy is still only 60... too bad potions don't leap the exp bar like silver rings (2) and enchant lockpicking or sneak or distruction with a petty gem will do.