The novel you were thinking of is
The 34th Rule, and it was coauthored by David R. George III and Armin Shimerman, the latter being the guy who played Quark.
I also recommend
Worlds of Star Trek: Deep Space Nine Volume 3, which contains two short novels, one of which is a Ferenginar tale by me called
Satisfaction is Not Guaranteed.
In addition, David A. McIntee will have a novella in next year's
Seven Deadly Sins entitled "Reservoir Ferengi." That'll be out in August.
