I recently went on a bit of an art supply bender (again)... and Sketch Calgary is one of the places closest to my house, so it's often the first one I hit when looking for supplies.
It's a great little shop, packed with almost everything you would need from dip pen nibs, water colours, Kolinsky brushes and markers to notebooks, palette knives and 2mm clutch pencil refills.
Lubica, the owner, is super friendly and knowledgable and offers truly awesome deals for artists, students and dabblers (like myself).
Since it's not a huge location, there are sometimes fewer brands then in a place like Kensington Art Supplies - but you can almost always find an equivalent replacement.