Some German bands I like are Agitation Free, Amon Duul, Amon Duul II, Ash Ra Tempel, Can, Cosmic Jokers, Dom, Faust, Fit and Limo, Gila, Golem, Harmonia, Kraftwerk, La Dusseldorf, Mandra Gora Lightshow Society, Out Of Focus, Popol Vuh, Tangerine Dream, Witthuser And Westrupp, Yatha Sidhra
The new beatsteaks album is a great punk record. If you like hip hop there's a lot to dig.Listen to Torch(great lyrics!!),Spax,Freundeskreis. I love the german downbeat stuff like Oh./Mo' Horizons,Jazzanova Electronic music is also big en alemania check out mouse on mars
If you're into alternative/crossover music, just listen to Guano Apes, Die Happy or H-Blockx. There's that guy who calls himself a hip hop hippie, but his music's more like reggae/folk-->Mellow mark. We also got a gothic band comparable to Evanescense or The Gathering called Xandria. the new beatsteaks album (smack smash) really rocks, too...
Mellow Mark is the cooles guy around. His music is reggae influenced but he uses a lot of street music, cuban music, hip hop, even psychedelic in one piece and so on. I've seen him life last year and there were such wonderful guitar solos... Another good band is the "Mandra Gora Lightshow Society".