Anywhere I can loot one? like off a corpse?

They keep kicking my ass. I want to get one for Ysolda side quest lol

You can definitely find them from other places. I believe I got one from a chest, but unfortunately I don't specifically know where I found it.

The trader in Windrun has one for sale and you can find a few in the Jarl's palace if you're not averse to theft.

In whiterun, there's a redguard that gives a quest to go retreive his father's sword, doing that quest will lead u to a cave in wich there will be mamoth tusks..

I stole one from the Jarl's quarters in Whiterun, but I also noticed a (much more difficult to obtain due to a lot of nearby npcs) tusk right behind the bar at the Whiterunn inn.

I found one on a desk in the DB sanctuary