
They were mentioned, but only a few times throughout the whole show. Once in "The Fifth Race" where Colonel O'neall [two Ls] meats the Asgard first hand and once in "Paradise Lost" where Colonel O'neall and Maybourne [no longer a Colonel] are stranded in a forgotten paradise that was deserted.
It was in "Paradise Lost" where at least we got a small glimpse of how the Furlings' technology looked like.
After that, poof.
You all know that I have the whole seasons 1-8 DVD sets, so I'm pretty darn sure about this.