Very confused and stressed

Hello,

I am new to this site, but I am finding the information I find very confusing and contradictory.

I am a British Citizen and my fiancé is Canadian and we are wanting to get married in October in Canada. I am currently in Canada until end of July 2011, I arrived 29 April 2011.

My fiancé spoke to CIC on the phone and was advised about the sponsor visa and that I can get an extension once I arrive back in Canada which is no problem and frankly good news that I won't have to keep travelling back and forth (I know I can be denied an extension but was advised if married the refusal rate is extremely low).

My main question is what do I say to immigration when I arrive in Canada and also why do they only ask you when you arrive why not ask while your still in your home country instead of making you travel 10hrs and then decide if you are allowed entry I find it ridiculous.

I don't have thousands in the bank etc and I have already stayed for 3 months on the VWP. My fiancé when he sponsors me will have to support me and he is now so I don't actually have any of my own funds I rely on him, as I know immigration ask if you work etc and how are you able to fund the trip.

Sorry for the long rambling thread, I am stressing out and having sleepless nights over this.

Thanks