for some awesome german music that you may not have heard about, look here: (disclaimer: german pop music is, when successful, slightly indie - in a good way!)
Klee: their new album is coming out these days, so this is my two favorite singles of theirs:
Mia: another act with a new album coming out these days, they are somewhat controversial, the singer is beyong obnoxious (especially in interviews) but the music is still good:
2raumwohnung: one of my favorite acts ever, these are pretty much their best songs, and "spiel mit" even has one of my favorite uses of space suits ever:
Samajona: It seemed like a band you would know, but i havent seen any mention of them yet. a now defunct girlband of 15 year olds singing in german. my favorite song though isn't on youtube - it has an inexplicably english chorus: "the car you wanna drive"