Hey Jeff. The forum is a good place to start looking for a Z06.
In fact, you'll find a couple on sale here.
http://forums.corvetteforum.com/show...postcount=1182
http://forums.corvetteforum.com/show...postcount=1214
But don't limit yourself to just the CDN side. Have a look in the US for sale forums. Very easy to import cars nowadays and there is alot of experience here for that.
Next would be to check your local dealers and autotraders. But be warned, dealers tend to charge a bit more than private, but sometimes, you'll find gems sitting on lots that just can't be passed up.
Then lastly, check out ebay, craigslist and kijiji. Buyer beware on these sites. Couple words of advice on the last 3.
1. Never pay with cash. You want some form of money trail in case the deal turns south.
2. Never go alone. Always have a friend or relative go with you when meeting interested parties.
I'm sure others will chime in with other suggestions, especially with anything specific to watch out for on a Z06.
Good luck on the search.
Stan.