TechLookz

Unlock Jason G:
During Chapter 4, go to the gas station, and there will be 3 gang members. Defeat them, and a cutscene with Jason plays. Beat him and he'll join.

Unlock Lola:
Chapter 2: Defeat any five Fatimas Saints, go to the police station and into the cell area, you will find Lola trapped inside. Rescue her.

Unlock Raven:
Chapter 4: Go to the southside park, and Raven may appear and challenge you to a fight, beat him. You only have one chance

Unlock Gina:
Chapter 5: Go to wharf and warehouse 12. Defeat all of the thugs with weapons and go to the storage room to rescue her.

How To Unlock Norma:
To unlock Norma you must defeat her in every chapter after the chapter, "Fatima's Saints." Chapter 3, she is located right outside The Hole, the first time it is impossible to miss her. Chapter 4, she can be found in Station Zone, this only works if you enter from the south WITHOUT a vehicle. Chapter 5, once again she can be found in Station Zone from the South enterance. Chapter 6, You have to exit Industrial Area South from the East, she will run up to you in the Town Square zone near the Industrial South Enterance, beat her there. Finally make you way to hotel zone and you'll get a call from her telling you to meet her at the basketball court, this time she will have a pride guage, unlike the last times, beat her up and then recuit her on to your team. If you miss her in any of these chapters, you will have to wait till you start the game again in a new game plus to get her.