Well there are a ton of products out there for city based encounters, but presuming you don't want to spend the money here are a few NPCs with plot hooks:
- Elis Myn, would be gang warlord - Elis Myn is a CN gang leader (Rogue/Fighter) with some actual good leanings. He lives in the poorest and most neglected region of the city and long ago accepted the brutality of life. Where he lives there is no justice without paying for it, those who seek to do good are only interested in spreading their religion or making a token effort for the sake of their own reputation, and things just continue to get worse. Elis had to belong to a gang to survive but now he leads one,the Razors, and is sick of seeing his part of the city run down and torn apart. He is organizing, drawing support with big ideas, and taking over the gangs by force when he has to. He has rules. Sell drugs to the rich, not your neighbors. Steal from those uptown, the poor don't have anything anyway. Fight amongst yourselves if you have to, but leave the other guy's family out of it. Elis is taking care of the people in his neighboorhoods, and is respected for it. Its safe for children to play now and the elderly to go out at night. There is even talk of him standing as a legit community representative to the Council. But the crime rates are going up in the rest of the city, mainly due to Elis' Rules and some time soon someone with some money and some power is going to get upset. He could be looking for some heavy firepower to hold off the enevitable raid, or someone may be looking to hire someone to take him down with out having to call in the troops.
- Fideous ap Gaereth (Paladin/Ranger) is one of the last remaining members of the disgraced Order of the Wall. They lost the city they guarded to a black dragon and scattered to the winds. Fideous was only a child when that happened and has grown up on the stories his mother told of the fabled city. He is fairly poor and shabby, but keeps his family heirloom weapons and armor in top condition. He takes his oath to the Order seriously. He will take any job that is respectable and pays. He is trying to rebuild the Order and thats going to take some cash. And maybe a few allies. On the other hand his constant attempts to rally support for his crusade are begining to embarass the nobles, as he is a popular figure among the citizenry. Maybe he need to have an accident one day in one of those dungeons.
- Korran Io (Bard), not his real name of course, is an information broker. He is just as much at home resarching in the University Library as he is singing in the finer brothels or gambling with goblins in the street. Korran knows everyone, can find anyone, and is nothing if not discreet. He works with the poor orphans of the city, and gets them to tell him secrets, and charms the noble's at their grand parties, and learns just as many there. He does, however, have a bad habit of sleeping with the wives and daughters of powerful men. Maybe he knows something the PCs need, maybe he knows too much, or maybe someone knows something about him.
- Elnisa (Fighter or Monk) was a dancer at a private club. She had been purchased as a child from her poor mother who had to sell her to feed the rest of the family. She has been, overall, treated reasonably well. She danced for wealthy men and women and was well paid. But when her owner refused to let her buy her freedom back they fought. In anger he branded her as a criminal and had her thrown into the gladiator ring. She won several boughts before escaping. Now she is a member of the Dianic League - dedicated to free all slaves and improving the role of women in society. She has powerful backers, who sometimes set her on less than noble tasks. She grows to distrust them and may seek the PCs for assitance in ending the slave trade or freeing herself from yet another form of slavery; or if they are working for the wrong person she may feel it neccessary to challange them.
Oh and a ton more, but thats enough for now.
You might want to check out
www.delverssquare.con - its the Ptolus fan site but has some interesting things in it all related to running a campaign in a city.