In general my supplemental fat sources come from the following:
Flax seeds (I despise the oil, but love the seeds), Fish oil, Almonds, Walnuts, Olive Oil.
That being said I generally eat one steak a day - usually flank, sirloin, or filet
And on occasion I treat myself to some sharp cheddar.
But in general, most of my fats come from the five sources mentioned above - but there are plenty of other healthy sources, so as mentioned before I would check out JB's article