Hi Abby,
I went to Montreal in 2013 and had a great time. There’s a street downtown called ‘Crescent’ where they had a fan festival, similar to what was in Austin in 2014. They basically take over the street with stalls and a big stage; I was able to get an autograph from David Coulthard. Also Will Buxton had his famous ‘tweetup’ in a bar about a block away. I don’t remember there being any music but it rained heavily during race weekend in 2013 (except race day) which put a bit of a dampener on it. Also I remember it was more of a Thursday-Saturday festival rather than a Friday-Sunday festival.
Check out this link:
http://crescentgrandprix.com/?page_id=7&lang=en
You’ll find up to date information there rather than my 2013 impressions!
Hope you have a great time!
George