Just Google "Prometheus 2". There's a version for 5.03 M33 Custom Firmware, and a version for 5.50 GEN D3 Custom Firmware, depending on whichever she has. Download the Prometheus 2 .rar package for her CFW, place the folder in the PSP/Game folder, run the installer on your PSP, and you should be able to play all the newest PSP games.
Nah, haven't gotten my copy yet. Since I'll be stuck in class for the next...4 hours, I've asked my dad to pick it up for me. So once I get home, I'll do data install, and start playing probably tomorrow in class.