Finally started playing this game and am just wondering if this DLC scales with your level.  Don't want to get in there and get completely annihilated.

I believe it does

Yes it does. And I believe the armor and weapons you get level up with you. Kinda weird but they do.

I think all of Dragon Age levels with you.  But I know that if you do the Warden's Keep you get a new weapon and at a higher level it is made out of a certain material and it happens to be the single best weapon in the game.