I think the reason there are no celebrities in town is because I'm using Twallen's Story Progression even though it says celebrities are allowed.
You must be playing a town where there are no "built-in" celebrities when you start the new game, right? Then, even if the celebrities are allowed, there is no-one to kind of... spread the disease, so to speak. (personally I don't like celebrities)
I think you need to manually add celebrity stars to some townies to get it started. I doubt any townies will move in with existing stars either, as the immigrants are propably CAS generated random sims. So if you have NRaas Master Controller, you can manually add some sims some stars. With only story progression, there is no way to do that... Or I think you could save some celebrieties to the bin (from other games/town) and then place them in the current one.
My sim has no celebrity stars and I never ever saw any opportunities (skill or celebrity) that had anything to do with celebrity points. So my feeling is they are only for after you gained the first star by talking to existing celebrities.