There is a glitch while playing the "TK Needs Zombex" level which will allow you to generate PP an unlimited number of times.
While at the clinic you can take a photo of TK. Shoot an image of the side of his head to receive 500PP. You can do this over and over again and still get 500 each time, allowing for potentially infinite PP, depending on your patience!
The following costume parts can be found by searching the indicated location. All costumes have the same function as in Dead Rising 2. The Protoman costume is a throwback to the original Dead Rising, except you have a shield as well as a cannon.
Boots: In the Man's Sport store in the Uranus Zone.
Clothes: Earn the 'Elite Killer' Achievement.
Hood: In a hidden room along the Ninja path in the Royal Flush.
Mask: On the mannequin by the entrance to Shoal Nightclub.
Boots: In the security room in Fortune City Arena.
Clothes: Defeat Carl in mail order Zombrex mission.
Mask: In the Wedding Chapel on the Silver Strip.
Hair: Watch the Timeshare movie in Paradise Platinum Screens in the Platinum Strip, from 12 a.m. To 2 a.m.
Boots: In a box in the vacant store to the right of the Ultimate Playhouse at South Plaza.
Clothes: Earn the 'Save the Girl...Again' Achievement.
Facepaint: In Shank's in the Palisades Mall.
Nightvision Goggles: Purchased in the Platinum Strip Pawnshop.
Cleats: In SporTrance in the Royal Flush Plaza.
Clothes: In KokoNutz Sports Town in Palisades Mall.
Facepaint: At the end of the Ninja path in the Americana Casino.
Helmet: In the back room of Hot Excitorama on the Silver Strip.
Helmet: Defeat Jack at strip poker in the Ante Up mission, or defeat him in Sandbox mode.
Armor: Earn the 'Challenge Experience' Achievement.
Boots: In the Ultimate Playhouse in the Palisades Mall.
Gun/Shield: Earn the 'Save the Girl Yet Again' Achievement.