Townsville itself doesn't have a whole heap of shows, but our zone (Far North Qld, or Zone 3) has a pretty good schedule of shows... Townsville is the middle point I guess of our zone- But most people travel four hours both south and North to attend more shows.
Check out: http://www.dogsqueensland.org.au/default.aspx for all Qld shows- but keep an eye out for Cairns, Atherton, Mareeba, Innisfail, Tully, Ingham, Townsville, Thuringowa, Proserpine, Bowen, Mackay which are shows that are held within a four hours radius of Townsville.
Our show season really only runs from late March to Early October due to our extreme heat up here though, so we miss a lot of the year...