Yes they get permission for all their songs
the whole glee cast
Yes. For example: Slash recently denied them permission to cover a Guns and Roses song.
Entitled "End Credits" (Made Famous by Glee Cast)
Glee Cast
No! From the Victorious cast.
Shout It Out Loud and Beth
the glee high school is in Ohio so that's why.
"Don't Stop Believing" by the cast of Glee.
It's called "Don't Stop Believin'" by Journey. Although in the commercial it's vocal version by the Glee cast. you can also get it on itunes.
The Glee cast performed the song "Landslide" in Season 2, Episode 15 titled "Sexy."
There has been reports that Glee will sing a song from The Wanted in the near future.
JUMP!