If you're looking for manga similar to The iDOLM@STER: Cinderella Girls Theater Extra Stage, you might like these titles.
Shy Niina Nijikawa loves to sing, but hates to perform—the thought of an audience scares her speechless—which leaves her dreams of being an idol dead in the water. But when a classmate introduces her to the world of VR, her world opens up...and she finds that becoming an idol—a VR idol—is within her reach after all!
Suuko, an idol-loving shut-in, has one ability: To make any idol popular through the power of blogging. She puts her sights on the Fukuoka idol Itrio and tries to make them sell more, but she is impeded by the charismatic otaku Ryu-san and the underground idol Mariko.
Green Leaves Entertainment is a tiny production company on the verge of going out of business in Sendai, the biggest city in Japan's northeastern Tohoku region. The agency once managed the careers of magicians, photo idols, fortune-tellers, and other entertainers, but its last remaining client finally quit. In danger of having zero talent (literally), the president Tange hatches an idea of producing an idol group. On the brash president's orders, the dissatisfied manager Matsuda heads out to scout raw talent. Matsuda makes a fateful encounter with a certain girl...
One day, 765 Pro idols Ami and Mami bring in the mysterious Petit-dols "Afuu" and "Yukipo"!? More and more Petit-dols gather at the offices where everyone works. Leisurely enjoy their daily lives full of laughs and happenings.