New to this game and was wondering where you can get something called Goo Armor? 

Any advice on how to get/make one? The fanguide doesn’t really tell you how

I don't think that's an actual item, are you doing the quest to get the dragon drunk because that has the closest thing I can think of.

Goo Armor is not an item, but a "buff" given by Chet. Take the Request to get Harken drunk. When you talk to Chet you got the option to be coverd in Goo,

Tipp: I prefer to undertake the Quest later in the game with high level and good gear. I say "No way!!!" to Chet and fight the Boss without Goo Armor for lvl points.