Nightwish, Therion, Within temptation, Leaves' eyes and other metal symphonic band fans help?!?

I have been to metal because I have heard their ballad songs first particularly Swanheart, Forever yours by nightwish ; Our Farewell by WT also Mourning tree by leaves' eyes and and Siren of the woods by therion.. please recommend me some song that sounds similar to those?? songs that gives you peculiar feeling because of its awsomeness.. if you know any bands with song like those please tell me.. your help will be much appreciated... thanks :)