I've seen a ton of mangas where the celebrity boy falls for the regular girl, but never the other way around. So I only want celebrity girl with normal boy. Someone help me? 😛

Try Love Lucky, Baka to Boing, or Koisome Momiji.

Ai ga Areba Ii no Da he does work in the biz though. He's an assistant director.
Cat Street?
also P.A.
Six Half maybe.
and Oboreru Knife? Though that's kind of stretching it. Kyou is hardly regular. Still worth reading though.

white album I think would be good one

Kodomo no Omocha
Charisma Doll if memory serves right :/

Favorite Art:
Oboreru Knife
19 Days
Gangsta

Not entirely sure if these apply to what you are looking for but;
I''s
Suki desu Suzuki-kun

And possibly Aozora Pop although the guy does work in the studio - I suppose he isn't really a celebrity though.

Thanks all so far, most of the suggestions were really good. Larinelle, I'm up to date with Suki desu Suzuki-kun!!! 😀 😀 One of my favorite mangas c:

It happens once in The World God Only Knows.