The eaziest way to create buzz before you have a prototype is to work on being internet famous.
All it takes is some writing talent, a blog and a time investment. Because, you know, launching things is much easier when you have a blog with 20k monthly uniques ... even easier when it's 100k monthlies.
That is to say, before there is a prototype, the buzz should be about you.
I certainly agree with you that being "internet famous" will help to generate buzz. I think the best scenario would be if the audience for your blog is similar as the target audience for your product. But I guess any buzz is better than nothing. :)
Setting up a landing page and doing a few basic things to draw attention to it should take you a day or less. You can either spend that time right away and have 500 people that care when you launch, or you can spend that time when you finish your MVP and launch and have no one that cares.
It's time you have to spend anyway, do it early, let it sit there and attract interest.
One thing you can't do when you finish your MVP is go back 3 months and have a landing page that attracted interest.
But that interest will arrive, whether it is to the landing page or to the actual application. Wouldn't it be better for the people to arrive at an actual product rather that a page requesting email addresses? I know that I never add my email address to landing pages.
All it takes is some writing talent, a blog and a time investment. Because, you know, launching things is much easier when you have a blog with 20k monthly uniques ... even easier when it's 100k monthlies.
That is to say, before there is a prototype, the buzz should be about you.