Well Hulu is the best site to stream all the tv shows just like Glee online. If you are from USA then just open the hulu and visit the show page of Glee. Here you will find all the latest videos of Glee including running season as well.

Glee On Hulu

But Hulu only restricts the country area. If you are from some other countries like Canada or UK then you can watch Hulu video using the following tricks:
How to access BBC iPlayer, Hulu, Fancast, Pandora, any other region-restricted sites


If you want to avoid ads, you can watch Glee on Amazon Instant Video


Hope it helps!!!!!!!!! Have a nice day