Not many NPCs in this one. There are a few though.
Name: Vodalian
Where: Random encounter in the village of Bywater.
Level: 6
Friendly: yes
Attacks: vs small/medium 1-5, vs large 1-5
Attacks/Round: 1
Special Attacks: -
Magic Resistance: 8 %
Armor Category: 10
Movement: 12
Regenerate: 0
Flags: magic using, intelligent
Immune to: -
Equipment: Robe of Protection +1, Quarter Staff +1, Dagger, Dart of Frost
Comment: -
My Comment: A friendly wizard you meet in Bywater. Keep him as long as he lasts. He's not very useful to any but the most inexperienced party.
Name: Great Wizard
Where: One in the kobold caverns to the South, one in the wizard's castle in Waterford.
Level: 12
Friendly: no
Attacks: vs small/medium 1-6, vs large 1-6
Attacks/Round: 1
Special Attacks: -
Magic Resistance: 25 %
Armor Category: 2
Movement: 12
Regenerate: 0
Flags: magic using, evil, intelligent
Immune to: -
Equipment: Robe of Protection +1, Bracers of AC 12, Staff of Fireballs +1
Comment: -
My Comment: Two of these around. Not very hard to beat, but don't use spells like cosmic blast against him as he has protection against 3rd level spells. The bracers are nice for low level enchanters and magic users.
Name: Rewop
Where: "In" the pentagram to the West in the kobold caverns.
My Comment: Summon him using the pentagram to the West in the kobold caverns. He'll bring two of his lieutenants. You should probably wait until all party members are at least level 4. His lieutenants have some nice stuff.
Name: Craggentooth
Where: Beyond a secret passage in the bugbear castle in Waterford.
My Comment: The chief of the bugbears who reside in a Waterford castle. You'll have to approach and help a bugbear mage in that castle to get to him. The battle is indeed a tough one so enter it fully rested and with your scroll cases ready.