I need to find an old friend in Hamburg Germany?

I really want to find an old friend in Hamburg Germany, I have an old phone number but she no longer lives there, and I can not do a paid search for a person as I do not actually know the address she used to live at in order to trace any further addresses she may have lived at, even worse she may be staying at friends (whom i do not know) at the moment so would not be listed at an address anyway. I can not seem to get a reponse from the email she used to use. I dont know where to look, I've tried the German phonebook but found nothing, is there a public record search I could use for Germany? Perhaps to see if she is registered to vote somewhere? Also, I'm afraid she might be dead as she was ill, is there anyway to search death certificates in Hamburg? I do not speak German either so any sites have to be at least translatable to English :-(