The book Expert Fishing - The Bass and You was used to teach expert fishing prior to patch 3.1. Once used, the fisherman could advance his or her fishing skill to 225.
This item was sold by in Booty Bay. You can still find Heming on the lowest level near the inn.
Patches and hotfixes
Patch 2.4.0 (25-Mar-2008): Removed the level requirement from the expert fishing book, The Bass and You.
Patch 3.1.0 (14-Apr-2009): Removed the item from the vendor. Expert fishing can now be learned from fishing trainers.