Mine was full upon receipt. It could be a dealer option to decide how much to fill, but I imagine they have a pre delivery checklist that has to be completed and I'm not sure if filling the DEF tank is one of them. It's not hard to fill it up though...
Off the self products, ICE makes some nice stuff. I've been buying everything online from a few different sites. ChemicalGuys.com is one, and AutoGeekOnline is another.
The spray foam is awesome to use!