At least you made a general thread of it, instead of just asking who they are.
I'll tell you now, it's much, much better to just encounter them. But I guess it can't be helped, so….
Iceburg is the mayor of Water Seven, and president of Galley-La, a shipbuilding company. He grew up under Tom, a Gyojin that built Gol D. Roger's ship, the Oro Jackson. He is smart, but kind of bummy at times. He's been hounded by the government for having plans for a great warship.
Pauly is a shipwright, "repairman," in the city of Water Seven. He specializes in rigging, and fights by using ropes to throw people. He hates scantily clad women, has a gambling problem, and acredits Iceburg for making him the man he is. We don't exactly have the details.
Franky is a man that wears a mask and resides in the outskirts of the city with his gang, the Franky Family. He initially robbed Usopp, but has sort of bonded with him after all that's happened in the city
There's some more, but I'm not sure how far you wanted me to go.
No, I'm not taking this back, because it took me a while to type.