Old Jed can be found in his house in a drunken stupor. He wants you to go purchase some wine to feed his habit and help his fishing. If you buy some wine for him from Pomab's Emporium he'll give you exp for completing this small task.
Better still you can get loads more exp if you talk him out of drinking his sorrows away. To do this you'll need a character with high Intelligence and decent Charisma (about 16 each). Have them talk to Jed to unlock the fairly obvious selections and talk him out of drinking. The bonus exp will be yours.