Brooklin and Ashburn are actually considered to be part of Whitby. They are located the north east of the city and within 1 hour commute. My wife was out in Ashburn yesterday at my sons riding lesson and then drove to her Moms in the city within 30 minutes. There is lots of beuatiful country living out that way.
Columbus and Blackstock are really a bit more of a commute.
Here is a link to Brooklin's website.
Brooklin, Ontario, Canada - Brooklin.org Home Page
Send me an email if you would like to discuss, or want more specific information.
good luck !