Hey Anthem,
I live about an hour away from Montreal and make the trip fairly often to visit my favorite cigar establishments. I have to agree with the others and say that a visit to Schwartz's is an absolute must. Best smoked meat in the universe!
If you're going to hit a few cigar spots, I strongly suggest the LCDH on Sherbrooke St. The selection is incredible, the lounge is beautiful and comfortable and the ladies working there are true connoisseurs. Stogies is great too, just not quite the same selection of cigars as LCDH, but much more selection to drink. I've been to Whiskey Cafe (for my bachelor party) and I think the prices are ridiculous ($55 for a Monte No.2!!) and the service is horrible.
Let me know if you need any info.
Paul