I get the German stuff out of Aldis. I forget the name. They do it right, 90% cacao. Very little sugar.
When you get to the 85% or higher range of dark chocolate, it's not cheap. Average price is $3 to $4 a bar. I can make a bar last about a week by breaking them into squares and freezing them. I'll have 2 or 3 squares a night with my red wine.