Slim pickings right now in Guelph for the type of house we're looking for, unfortunately. We've looked at a few, and there's a few more quite nice ones, but way too close to the hospital for comfort. We actually tried to get one that would have been great, but it already had a conditional offer on it that the other buyers firmed up (looked at it one morning, flew to Edmonton that afternoon, and were faxing offers back and forth that evening.. busy day).
Thought about building, but decent lots for small custom builders are hard to come by (and for the hassle, at this point our preference is that we'd rather buy than build anyway). Unlike K-W, Guelph actually does a really good job of managing growth in an intelligent and much more sustainable way.
We'll keep an eye on the market for the next little while anyway...