Well the postmaster looked after sendmail, that being the old word for the man in charge of the post office. The hostmaster looked after DNS because it rhymed, and they needed a word for the guy who looked after the website.
It was a very different meaning from today's "rockstar ninja".
Funny. The term is still in use; I think it's usually meant to imply a deeper level of ownership, a la sysadmin. A few times a year people contact me saying they need a webmaster, and the way they describe their needs, I wouldn't say that "developer" really covers it.
I thought homepage was just whatever page you had your browser set to start up on. And then some of us built personal home pages that had all the links we cared about on them. And then one of us built Personal Home Pages.