Eggman has been staging concerts in Shibuya already since 1981.
They mainly host up and coming Japanese bands, often rock music.
Address 1-6-8 Jinnan Shibuya
Telephone +81 (0)3 3496 1561
Website (In Japanese but they use so much English you will still be able to figure out the schedule) http://eggman.jp/
Business Hours depending on shows, but usually starting late afternoon-early evening