I'm able to show more than a handful german singers and bands, but I'll start with a recent one.
Jupiter Jones
A 4 man punkrock band, founded in 2002.
They're known for their deep and great lyrics and also for the unique voice of leadsinger Nicholas Müller.
After three indie albums, they finally got a contract with Sony Music Germany. Their first major album called "Jupiter Jones" was released on 25th February 2011, followed by the first major single "Still" (english Quiet or Silent) on 4th March this year. "Still" is a big success, managed to get in the top 10 on the charts and being one of the most played radio tracks in the last three months.
"Still" is a meaningful mid-tempo ballad and though being absolutely not punkrock also part of their partly mixed style. It's originally about the death of Nicholas Müllers mother and loss in general.
Here's the official video for "Still":
Other songs:
Das Jahr in dem ich schlief
Alles Glück der Welt
Wir sind ja schließlich nicht Metallica
I highly recommend them, although her overall work isn't as (mainstream) pop as "Still" indicates.
Their major career just started and I'm really curious how their career will go on.