Is it good to buy a .ca domain and duplicate my .com website on it to increase my seo rankings in Canada?
Thanks.
Buying a .ca domain and duplicating your website will do absolutely nothing for your rankings. However, if you have two different offices or two different types of content (even if they’re similar) then having different TLD’s can be useful. Google will be smart enough to know that your .ca is targeted to Canadian users and your .com is targeted to the USA. You would want to be sure to change the mailing address and telephone numbers on each website accordingly.
If you are going this route, you’ll also want to setup each domain within Google Webmaster Tools and associate the domains with their target country respectively. While Google should be smart enough to figure this out, it never hurts to be sure.
If you don’t have different content then don’t duplicate the website. It still might not be a bad idea to buy the other domain and 301 it back to your primary domain to protect your business name.
IMHO more then doing good it may harm you if Google or other Search engines catches it as Duplicate content.
If your site is specific to Canadian audience then you can set that in your Google Webmaster control panel for that particular domain. But if your content appeals to world audience and you want that then would suggest not to do that.
However would like to read what other people has to say on the same.
Google will not harm either site for duplicate content. If Google finds duplicate content the site that it determines to be unoriginal will simply not be indexed.
if you qualify to obtain a .ca name, then yes, you should definitely get one
if you don’t qualify, you can’t get one
simple, innit 
see http://en.wikipedia.org/wiki/.ca for canadian presence requirements
Well if Google determines that its unoriginal then it will not index the duplicate site then isnt it actually harming and wasting the whole effort.
And if both sites are interlinking and the .CA comes under Google scanner as “bad neighbourhood” will it not harm the original domain?
Having an exact copy of your duplicate content not indexed isn’t doing any harm, it’s just not doing any good either. The owner of the two websites won’t be any worse off then he/she was by having just the single copy. This circles back to my original point which was why duplicate the content in the first place? If there is nothing new or different about the content on the additional domain then there’s no point in copying it.
Why would you interlink the domains? I can understand having a single link on the contact page to the other office (website) but that’s it. If you’re linking back and forth across domains then you’re just asking for problems. Not only does it look spammy, but what if one of your websites goes down. The other is now also unusable. Google is going to look at it from the user perspective. Why would this website be cross linking to another domain that hosts exactly the same content? I can’t see any reason to interlink the sites.
Well many sites do interlink to get it spidered by the search engines and to pass a little PageRank juice to his other domains.
I guess we are talking the same thing that getting another domain with the same content is not going to do any good and wont help in targetting a specific country (if the content is same). And as I said if its not getting indexed then its doing harm only and wasting whole effort of setting up another domain and managing it. [:)]