Kat with a K

You might try lastfm.com where you use music/artists you like to find similar stuff. And iTunes always has two or three free songs you can download from their website each week.

I like to go through iTunes' "Essentials" playlists for ideas, and then buy a few things, and then follow their recommendations for me based on the things I've bought.

To answer Q.1: Regina Spektor, Brandi Carlile, The Raconteurs, Blue October, and Vienna Teng are in pretty heavy rotation right now, along with the usual hodgepodge of 90's alternative and 80's pop.

I have really wide-ranging tastes in music so this might not work for you, but I go for pretty much anything NPR or Bust recommends (NPR is nice because you can listen to clips on their website
--although come to think of it I think you can with Bust now too). I also like to browse the CDs at the Manchester Library, because they have enough that there's variety but not so many that I get overwhelmed. And I don't have to buy them so there isn't any risk involved. Also if I'm at Barnes and Noble I do that scan-the-CD-and-listen-to-blips-of-the-songs thing--and then if I like it I buy the CD at Newbury Comics, since they're cheaper.