No, they don't have an API, you just have to be a little, uhm, creative
I follow Kevin's blog pretty closely and I know his views are pretty much 100% similar to my own (probably why I enjoy reading it), and likes to refer to long term fundamentals, long term prices after adjusted for inflation, etc. As well as metrics such as price/rent ratios, median income to home price ratios, etc.
The amount of work he puts into his blog is immense, and he does a good job of taking large amounts of data and interpreting it for the masses. And it's actually a pretty funny read from time to time. One of the more 'personal' posts he made recently was regarding the inevitable real estate conversations that would come up when gathering with his friends...
"Unpopular Opinion"
http://edmontonhousingbust.com/2010/...pular-opinion/
From everything I've gathered, he's of the belief that Edmonton is about 20-25% overpriced relative to long term fundamentals. He's also of the belief that when corrections occur, or bubbles pop, they tend to overshoot by a bit, and things actually become undervalued.
20-25% is also exactly how much I feel Calgary is overvalued at the moment. Just based on our own long term fundamentals as well, price/rent ratios, long term price increases, median wages, etc. Pretty much every fundamental I can think of points to us being around 25% overvalued.
Of course, we all know that predictions are meaningless, and markets are anything but rational.