Will you be renting a car? If you want to visit Montreal and Québec City, it might be more worthwhile to fly directly to one of those two cities in order to save yourself a day of driving from Buffalo.
I’m sorry I can’t recommend cheap accomodations, since I live here and have friends/family in all three of these cities, so that’s where I stay when I travel! I can, actually, recommend one good campground just outside Québec City - Camping Juneau in St.-Augustin-des-Demaures. It’s probably a 15-20 minute drive to downtown, but it’s right on highway 40, so it’s really easy to get to from Montreal. Nice camping spaces, very clean showers and washrooms, and good pricing. I’ve stayed there a few times, but less because we wanted to see the city than because we wanted to have a campfire and drink ourselves silly with friends.
As for nature in the city; Montreal’s Biodomeshould be able to take care of that, along with a walk on Mount Royal. The Old Port (of both cities, actually) are worth a visit, and there are plenty of terrasses and good food to be had pretty much anywhere.
Beer: Perhaps the most well known will be the Unibrouebrewery, based in Chambly (about 20 minutes from Montreal), though they are easily found in a lot of restaurants, bars and dépanneurs across the province. The Fourquet Fourchette restaurant downtown has some very good food and most, if not all, of the unibroue selections.
Dieu du Ciel also makes some fantastic beer, and has a nice pub on Laurier street, near St-Laurent Blvd. I need to go there again…though I observe that their website isn’t exactly awesome.
Les 3 Brasseurs (WARNING STUPID ADVERTISNG MUSIC is a bit of a chain of restaurants/brewpubs around Montreal, though I note they are expanding to Toronto - they have a couple of locations right downtown and are a favourite amongst McGill and Concordia students (from what I’ve seen!) I love their Amber beer.
I have yet to try Benelux…really no excuse, as they are a very short direct bus ride from my place.
You can’t go wrong with McAuslan, which makes fantastic beer and is a sponsor of my dragonboat club. Drink their stuff.
You might findthis list useful.
If you want to load up on Québec beer without trying to hit every brewery in the province, may I recommend this dépanneur? They specialise in Québec beer. The beer guy is there most evenings and weekends, and speaks Passable English. They carry some fantastic beer, but also some weird-ass brews that should only be consumed for the sake of saying that you did so. Oh, and they carry beer from Lennoxville’s Golden Lion Pub, my first drinking “home” (legal, anyways…!)
As for cash, the Canadian dollar is rather strong right now. Your American bucks won’t go as far as they would have a few months ago, but who knows where the world will be in August. Check your bank/debit cards - on the off chance that they are Interacenabled (look for that logo on the back), then you can use those pretty much anywhere (we love our Interac system), but most merchants will take either MasterCard or Visa… American Express is a little less likely to be accepted. You can exchange money very easily in both cities.
If you do go to Québec City, check to see if the Moulin à Images will be playing while you are there. They developed this last year for the 400th Anniversary, and are bringing it back this year because it’s was so well-received. It visually shows Québec’s history and culture…it’s truly amazing to watch.