How to find the perfect ceremony venue???

If you're not Catholic, check with the United Church. They would marry you without the hassle. It's more expensive if you're not a member but if you want a church, try that one.

The Catholic church may be tough because one of you needs to be Catholic. You could always attempt to speak with the priests at the church to see what the options are with the location, but just be prepared that the may not be super flexible with what the expectations are with getting married there. I don't want to put a damper on it, but the church can be a little strict.