Try buying an album with Jeannette McDonald and Nelson Eddy, who sang duets years ago--I think you're looking more for "operetta" which is somewhere between Broadway show tunes and opera. They are light and express themselves in an operatic manner. By the way, it's true that anyone can extend their vocal range considerably through lessons and practice over a long period of time. I was able to extend my range an octave. Female voices would be from high to low--coloratura soprano, lyric coloratura soprano, lyric soprano, mezzo soprano, contralto. The coloraturas can generally get up to high F's, and lyrics to a D or E flat, but good mezzos can also get up to high D. The voice is more characterized by the quality of the sound and the heaviness of the weight of the voice. Coloraturas usually have lighter voices, enabling them to easily do rapid runs. A heavily voiced lyric or a dramatic soprano could be said to have a lot of power in their voice, but the voice may be difficult to move in the case of runs due to its weight. People are always trying to categorize singers, but sometimes there are voices like Joan Sutherland which seem to break the mold. She has been labeled a dramatic coloratura soprano due to the weight of her voice and the ease with which she could do runs. Enjoy your hunting!