Help me discover some new music...

The Sea and Cake
Sam Prekop
David Sylvian
Mick Karn
David Torn
Marillion
Vinicius Cantuaria
Eduardo Paniagua

I highly recommend you check out some classical music. Small-scale Mozart and Bach will sound great on your system. String quartets, violin/piano, violin/harpsicord/cello. They will sound fabulous on your system and there are tons of mint used records available at very reasonable prices. I think many people are put off by classical from attempting to listen to large-scale symphonic music. It's long, ponderous and difficult to reproduce on smaller systems. The small stuff was mostly written as background music for the royals and it's very easy to listen to. The music is beautiful, relaxing and itt just fills the space with tranquility. Can't ask for more than that, can you?

+1 David Sylvian! My favorites of his are:
Nine Horses - Snow Borne Sorrow
David Sylvian and Robert Fripp - Damage

Both are seriously great.

Rebbi - Someone started a best of 2012 thread. Check it out. New to me from that was the band, "Calexico". From Calexico, I stumbled onto, "Big Lazy". They both might be making music you will enjoy.

Rebbi do you use Spotify or MOG? It's free but with commercials every 5 songs or so. My wife and I pay ten bucks for premium service. No commercials and we have access on our iPhones and iPad and can just hook right into my main system, or listen on the go or in the car.I highly recommend this approach for you as you have access to 30 million songs and really complete catalogs from most major artists. You can sample tens of thousands of musicians before you buy CDs or decide to listen to Spotify or MOG without buying the CDs . Spotify and MOG do offer suggested material when listening to an artist.
Here are other great ways I find new music.
Pitchfork , online music mag. Search for the best reviewed albums, although they have panned albums I find near perfect.
Best of music threads here. I discovered Ben Howard this way.
On AudioCircle I look at what are you listening to now threads. Also in the Salk Circle there is a fantastic thread on reference recordings with great music of course.
NPR , First Listen and Tiny Desk Concerts and listen to public Radio.
My wife explores a lot of new music and sends me the bands she thinks I will like. Lucky my wife is a musicphile.
As others gave mentioned , branch out from classic rock to Alternative Pop, Alt. country has been a revalation for me and I dislike Country music. I discovered Jazz a few years ago as well. Blues and Bluegrass can be great as well. I listen to a lot of male singer song writers such as Ray Lamontagne and David Grey, Martin Sexton etc.
Sample, listen, explore, branch out, and most importantly discover new music that makes you happy.