I put mine on ad hoc and nobody joins a game, I have GTA Vice City Stories but nobody has a game or nobody joins mine. I believe it's been a long time and maybe nobody plays it anymore, but I look on the Platstation Network and it is one of the top games so of course at least one or two people would be curious to go on the multiplayer.
Please help, thanks!
No one joins you because Ad-Hoc is locally. You aren't connected to the internet. Infrastructure is what you need for Online Play, and not too many PSP games have that.
Through Xlink Kai it doesn't have to be locally. But then again i don't know how many people play PSP games over Xlink.