As Michael B noted, I've really, really enjoyed the Wild Planet tunas.... kinda expensive, but when you open a can (I prefer the lightly salted Albacore) you can really taste the tuna flavor. It is similar to the ones Karen had mentioned (west coast guys who can their own caught tuna).
We're lucky to have two sources of this in town, and occasionally they go on sale... I usually stock up.
And, yes, supposedly troll-caught and they use the smaller tuna so supposed to have a lot less mercury in it. Dolphin-safe of course.
I've built up a list of several west coast fishers/canners who do similar and when I'm flush with some cash, I plan to order directly from a source.
This is one list that has a bunch of small folk who fish tuna and offer their products for sale:
http://www.albatuna.com/Sources/Canned.htm Kinda fun just to read through some of the websites and their products.
Thanks,
Mike