Alright, looking over the fighter power selection the following levels should have a weapon based power for staves
3, 13, 23

I see Staves as lot like Ax's and able to do sweep blows, but I also see them as defensive weapons, so.

Level 3
Cobra Strike Fighter Attack 3
Encounter<>Martial, Weapon
Standard Action Melee Weapon
Target: One Enemy
Attack: Strength vs. AC
Hit: 1[w]+Strength you gain +2 power bonus to your AC until the end of your next turn
Weapon: If you are wielding a staff, you gain a bonus to AC equal to your dex modifier until the end of your next turn

Level 13
Flash Blow Fighter Attack 13
Encounter <> Martial, Weapon
Standard Action Close Burst 1
Target: All enemies in burst you can see
Attack: Strength Vs AC
Hit: 1[w]+Strength
Weapon: If you are wielding a staff, add you gain a bonus to damage equal to your Dex modifier

Not sure for level 23 yet.