I don't listen much to polish music because I have somewhat.. odd music taste. I refer to it as to bands with yelling women as vocalists. That means, I like classical female voices, and the quite interesting thing is that they often sing in metal bands. My favourite is Nightwish, they're from Finland.
A polish band- Herjalf, they're undergorund but they vocalist is great. There are some mp3's to download from their site:
www.herjalf.metal.pl I recommend Stary Smok and W Majestacie Mrozu. Tell me what do you thnk about them. But I warn you, if you don'tlike operatic voices, you will probably don't like it