I used to be big into the whole urbex thing but just haven't had much time for it in the past few years. It seems I'm not alone - most of the online resources have dried up recently but there is still some information out there. It's not so much ghost towns as just abandoned places in general, but man there is some fantastic stuff out there. Check out
www.uea.ca.
There is also a database of abandoned places at
www.uer.ca. The site is kind of hard to navigate and much of the information can only be viewed by members as the *ahem* "illegal" nature of some urban exploring makes people understandably wary of who they share their finds with, but still worth a look. Lots of cool stuff right here in southern Alberta or an easy drive away in southeastern BC.