As kris mentioned in elephänt: epitonic is really cool. I've made a playlist of some tracks I've found there (the playlist starts with guitar-songs and moves to more dance-able tracks). Maybe you have some more suggestions.

i went to the "radio" page and filled my itunes with houndreds of songs. after listening to about 100 of them i marked at least 20 as [this is good]. my current favourite is blue six, which is sexy deep house with great female singers. their latest cd is brilliant.