It's far from impossible to change your voice. Changing the pitch is a relatively easy process but the work is in making it sound realistic. Our ear determines the gender of the voice based on the pitch and the speech pattern. If you only raise the pitch without changing the speech pattern, the voice sounds high pitched male. Often you can have a woman with a very low voice but a feminine speech pattern sound feminine. A trained (or at least educated) ear is require to make adjustments in the voice. When I have the time, I will spend time in the voice forum evaluating voices, many that were self trained.
A surgical voice is half surgery and half therapy. In my view, surgery is an important aid in those of us who's voice is so low that it's not possible to comfortably maintain a feminine voice. Surgery shouldn't be considered until you know what you have to work with and what is or is not possible with your voice.
