My current party has three fighters and a Ninja and so needless to say, I'm looking for some good weapons. I'm familiar with a lot of the good primary weapons but I haven't found any good secondary weapons to use ( all my guys are training dual weapons ).

Any suggestions....

(I'm still pretty early in the game...I'm at Martens Bluff for the first time).

I don't know much about the Ninja, but here is a list
of all secondary weapons useable by a lizardman fighter
afaik.

Dagger Skill Weapons:
Canezou Dagger
Dagger 1-4(1d4+0) Init:4
Baselard 1-7(1d7+0) Init:2
Main Gauche 1-5(1d5+0) Init:3
Poignard 1-8(1d8+0) Init:2 TH:1
Serpent's Tooth 3-13(2d6+1) Init:3 TH:2 Poison%60

Mace & Flail Skill Weapons:
Diamond Eyes 7-22(3d6+4) Init:3 TH:2 Paralyze%20
Hammer 3-8(1d6+2) TH:-1
Stun Mace 3-8(1d6+2) Init:-2 DrainStamina%25
Flame Quencher Wand 1-8(1d8+0) Init:5 TH:1 Paralyze%5
Notched Staff 1-3(1d3+0)
Shillelah 1-6(1d6+0) Init:1
Thunder Stick 4-10(2d4+2) Init:5 TH:1
Wand of Static 1-8(1d8+0) Init:5 TH:1
Wand of Winds 6-10(2d3+4) Init:5 TH:1
Winter Wand 4-8(2d3+2) Init:5 TH:1 Paralyze%15
Wooden Dowel 1-3(1d3+0)
Ymmu's Paw (cursed) 5-10(1d6+4) Init:5 TH:1 Hex%15

Axe Skill Weapons:
Bearded War Axe 1-6(1d6+0) Init:1

Throwning & Sling Skill Weapons:
all except Shuriken, Boomerang Shuriken, and Death Star

Helix

There aren't that many good secondary weapons.

For fighter types, the single excellent one is Diamond Eyes. Found fix in the mountain wildernesse, and may be found in the drop of a friendly NPC.

Most common secondary weapons are daggers. IIRC Stiletto can be wielded off-hand, has 1-8 damage, and 10% kill.
For damage, Canezu Dagger is best.
And there are some wands. See Helix' list. Best one IMO Winter Wand (for the Paralyze Chance).

For the ninja, there exist several cheap secondary weaypons. Ninjato, Sai, Nunchaka. Not high damage, but good ko or kill chance. Sometimes Crock sells Nunchakas.

A word to Heliox' list:
Some of the weapons can probably not be found in Wiz8, they are only imported from Wiz7. And some have additional restrictions (Serpents Tooth is only for specific races). And Stun Mace is primary only (as you probably already found out).

I wouldn't use 3 fighters in a party (normally; once i played 3 fighters + 1 bishop). Samurai has nice secondary weapon (enchanted wakazachi). Monks and Ninjas can fight with hands and feet. For fighter types, i'd only use dual with one fighter (the mace&flail type; will use Mauler + Diamonds Eyes later). The sword fighter might use a shiled. The Axe fighter is best with two-handed weapons.