Amy Macdonald is currently on high rotate for me. Similarly other females-with-a-[your instrument goes here]. It's a thing for me.
But having said that, I've recently realised that the key factor in most of the music I like is that... I can sing along. I love music and singing. I'll never be any kind of Idol, and wouldn't even get to the televised auditions of a tv show - because I'm not *awful* but I also have no delusions at all that I'm any more than vaguely tuneful.
So most of the music I listen to is music that's in the right key for me to dance around and sing to. Ani difranco is a big one for me. I'm definitely in the camp which prefers her older material, and I can sing along to all of Not A Pretty Girl and Not So Soft. I think she has some really important messages about being a strong woman etc - but even more helpfully her range is very similar to mine. If I'd had to squeak to sing along, I don't think her music would have stuck so much.
So the singers who go way up into the rooftops with their octaves and sopranoism are out of reach for me. So I stick with Amanda Palmer and Ani and Amy. The Whitlams are another band who make music in approximately the right key for me. Sometimes I have to modulate, but overall I can sing along.
The best thing for me is when I'm not tired and not distracted, and can go for a nice long drive, singing to my favourite songs and enjoying the road and the music and where they both take me.